<PAGE>   1

                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON D.C 20549

                                    FORM 10-Q

[X]   QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934

                  FOR THE QUARTERLY PERIOD ENDED AUGUST 5, 2001

                                       OR

[ ]   TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934


                         Commission file number 0-21296

                       PACIFIC SUNWEAR OF CALIFORNIA, INC.


                 CALIFORNIA                             95-3759463
          (State of Incorporation)          (I.R.S Employer Identification No.)

          5200 EAST LA PALMA AVENUE
             ANAHEIM, CALIFORNIA                           92807
   (Address of principal executive offices)             (Zip code)


                                 (714) 693-8066
              (Registrant's telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports); and (2) has been subject to such filing
requirements for the past 90 days.
                                                             YES [X]     NO [ ]

     The number of shares outstanding of the registrant's Common Stock, par
value $.01 per share, at September 6, 2001, was 32,736,273.

<PAGE>   2

                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                                    FORM 10-Q

                      FOR THE QUARTER ENDED AUGUST 5, 2001

                                      INDEX

                                                                           PAGE
                                                                           ----
PART I.   FINANCIAL INFORMATION

Item 1.   Consolidated Financial Statements:

            Consolidated Balance Sheets as of August 5, 2001 (unaudited)
              and February 4, 2001..........................................  3

            Consolidated Statements of Income and Comprehensive Income
              (unaudited) for the second quarter and first half ended
              August 5, 2001 and July 30, 2000..............................  4

            Consolidated Statements of Cash Flows (unaudited) for the
              first half ended August 5, 2001 and July 30, 2000.............  5

            Notes to Consolidated Financial Statements......................6-7

Item 2.   Management's Discussion and Analysis of Financial Condition
            and Results of Operations......................................8-14

Item 3.   Quantitative and Qualitative Disclosures About Market Risk........ 14


PART II.  OTHER INFORMATION

Item 1.   Legal Proceedings................................................. 15

Item 2.   Changes in Securities and Use of Proceeds......................... 15

Item 3.   Defaults Upon Senior Securities................................... 15

Item 4.   Submission of Matters to a Vote of Security Holders............... 15

Item 5.   Other Information................................................. 15

Item 6.   Exhibits and Reports on Form 8-K.................................. 15

          SIGNATURE PAGE.................................................... 16


                                       2

<PAGE>   3

                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                           CONSOLIDATED BALANCE SHEETS

                                     ASSETS

<TABLE>
<CAPTION>
                                                              AUGUST 5,       FEBRUARY 4,
                                                                2001             2001
                                                            -------------   -------------
                                                             (unaudited)
<S>                                                         <C>             <C>

CURRENT ASSETS:

  Cash and cash equivalents (Note 2)                        $   3,711,579   $  28,971,240
  Accounts receivable                                           5,615,196       2,754,119
  Merchandise inventories                                     124,273,984      82,692,992
  Prepaid expenses, includes $7,549,456 and
    $6,663,284 of prepaid rent, respectively                    9,493,271      10,187,317
  Deferred taxes                                                2,991,765       2,991,765
                                                            -------------   -------------
    Total current assets                                      146,085,795     127,597,433

PROPERTY AND EQUIPMENT:
  Land                                                         12,156,221      12,156,221
  Construction in progress - new corporate
    office and distribution center                             12,150,252              --
  Leasehold improvements                                       93,940,866      83,770,420
  Furniture, fixtures and equipment                           102,209,517      92,409,132
                                                            -------------   -------------
                                                              220,456,856     188,335,773
  Less accumulated depreciation and amortization              (62,568,547)    (52,553,794)
                                                            -------------   -------------
    Net property and equipment                                157,888,309     135,781,979

OTHER ASSETS:
  Goodwill, net of accumulated amortization
    of $1,452,007 and $1,296,325, respectively                  6,647,758       6,803,440
  Deferred compensation and other assets (Note 3)               7,475,660       7,269,727
                                                            -------------   -------------
    Total other assets                                         14,123,418      14,073,167
                                                            -------------   -------------
             Total assets                                   $ 318,097,522   $ 277,452,579
                                                            =============   =============

                     LIABILITIES AND SHAREHOLDERS' EQUITY

CURRENT LIABILITIES:
  Line of credit (Note 4)                                   $  11,075,000   $          --
  Accounts payable                                             40,263,308      31,631,805
  Accrued liabilities (Note 5)                                 15,226,134      13,251,419
  Current portion of capital lease obligations                    535,798         488,472
  Income taxes payable                                          1,587,394       2,427,165
                                                            -------------   -------------
    Total current liabilities                                  68,687,634      47,798,861
Long-term debt - construction facility (Note 4)                 9,000,000              --
Long-term capital lease obligations                               800,230       1,102,857
Deferred compensation                                           6,752,326       7,268,377
Other long-term liabilities                                        28,316          28,316
Deferred rent                                                   7,800,424       7,210,923
Deferred taxes                                                    912,012         912,012

SHAREHOLDERS' EQUITY:
  Preferred stock, par value $.01; authorized, 5,000,000;
    none issued and outstanding Common stock, par value
    $.01; authorized 75,937,500 shares; issued and
    outstanding, 32,729,331 and 32,441,435 shares,
    respectively                                                  327,293         324,414
 Additional paid-in capital                                    87,619,946      81,161,034
 Retained earnings                                            136,169,341     131,645,785
                                                            -------------   -------------
   Total shareholders' equity                                 224,116,580     213,131,233
                                                            -------------   -------------
             Total liabilities and shareholders' equity     $ 318,097,522   $ 277,452,579
                                                            =============   =============
</TABLE>


                             See accompanying notes


                                       3

<PAGE>   4

                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                      CONSOLIDATED STATEMENTS OF INCOME AND
                              COMPREHENSIVE INCOME
                                   (UNAUDITED)

<TABLE>
<CAPTION>
                                              FOR THE SECOND QUARTER ENDED      FOR THE FIRST HALF ENDED
                                             ------------------------------  ------------------------------
                                             AUGUST 5, 2001   JULY 30, 2000  AUGUST 5, 2001   JULY 30, 2000
                                             --------------   -------------  --------------   -------------
<S>                                          <C>              <C>            <C>              <C>
Net sales                                     $156,508,718    $131,969,736    $294,206,673    $244,531,175
Cost of goods sold, including buying,
  distribution and occupancy costs             108,330,880      88,185,078     204,072,250     162,852,073
                                              ------------    ------------    ------------    ------------
Gross margin                                    48,177,838      43,784,658      90,134,423      81,679,102
Selling, general and administrative
  expenses (Note 8)                             42,436,750      31,901,745      83,038,730      60,647,843
                                              ------------    ------------    ------------    ------------
Operating income                                 5,741,088      11,882,913       7,095,693      21,031,259
Net interest income                                 12,030         168,817         246,863         506,503
                                              ------------    ------------    ------------    ------------
Income before income tax expense                 5,753,118      12,051,730       7,342,556      21,537,762
Income tax expense (Note 6)                      2,209,000       4,681,000       2,819,000       8,362,000
                                              ------------    ------------    ------------    ------------
Net income                                    $  3,544,118    $  7,370,730    $  4,523,556    $ 13,175,762
                                              ============    ============    ============    ============
Comprehensive income (Note 1)                 $  3,544,118    $  7,370,730    $  4,523,556    $ 13,175,762
                                              ============    ============    ============    ============
Net income per share, basic
  (Notes 7, 8)                                $       0.11    $       0.23    $       0.14    $       0.42
                                              ------------    ------------    ------------    ------------
Net income per share, diluted
  (Notes 7, 8)                                $       0.11    $       0.23    $       0.14    $       0.41
                                              ------------    ------------    ------------    ------------
Weighted average shares outstanding,
  basic (Note 7)                                32,719,399      31,760,227      32,619,110      31,651,616
                                              ============    ============    ============    ============
Weighted average shares outstanding,
  diluted (Note 7)                              33,101,815      32,316,649      33,135,948      32,451,217
                                              ============    ============    ============    ============
</TABLE>


                             See accompanying notes

                                       4
<PAGE>   5

                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                      CONSOLIDATED STATEMENTS OF CASH FLOWS
                                   (UNAUDITED)

<TABLE>
<CAPTION>
                                                                       FOR THE FIRST HALF ENDED
                                                                  ----------------------------------
                                                                  AUGUST 5, 2001       JULY 30, 2000
                                                                  --------------       -------------
<S>                                                                <C>                  <C>

CASH FLOWS FROM OPERATING ACTIVITIES:
Net income                                                         $  4,523,556         $ 13,175,762
Adjustments to reconcile net income to net cash
  provided by operating activities:
  Depreciation and amortization                                      12,752,374            8,904,154
  Loss on disposal of equipment                                       4,179,336
  Change in operating assets and liabilities:
    Accounts receivable                                              (2,861,077)          (3,690,118)
    Merchandise inventories                                         (41,580,992)         (36,202,242)
    Prepaid expenses                                                    694,046             (679,552)
    Deferred compensation and other assets                             (456,833)             147,653
    Accounts payable                                                  8,631,503           21,994,633
    Accrued liabilities                                               1,974,715             (181,295)
    Income taxes and deferred taxes                                   1,645,237              443,600
    Deferred rent                                                       589,501              661,024
                                                                   ------------         ------------
        Net cash (used in)/provided by operating activities          (9,908,634)           4,573,619

CASH FLOWS FROM INVESTING ACTIVITIES:
  Investment in property and equipment                              (38,857,354)         (25,644,766)
                                                                   ------------         ------------
        Net cash used in investing activities                       (38,857,354)         (25,644,766)

CASH FLOWS FROM FINANCING ACTIVITIES:
  Net borrowings under credit agreement                              20,075,000                   --
  Proceeds from exercise of stock options                             3,686,628            1,858,052
  Principal payments under capital lease obligations                   (255,301)                  --
                                                                   ------------         ------------
        Net cash provided by financing activities                    23,506,327            1,858,052
                                                                   ------------         ------------

NET DECREASE IN CASH AND CASH EQUIVALENTS:                          (25,259,661)         (19,213,095)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD                       28,971,240           32,416,794
                                                                   ------------         ------------
CASH AND CASH EQUIVALENTS, END OF PERIOD                           $  3,711,579         $ 13,203,699
                                                                   ============         ============

SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid during the period for:
  Interest                                                         $     39,089         $      1,008
  Income taxes                                                     $  1,173,763         $  7,918,400
</TABLE>

--------------------------------------------------------------------------------

Supplemental disclosures of non-cash transactions: During the first half ended
August 5, 2001 and July 30, 2000, the Company recorded an increase to additional
paid-in capital of $2,485,008 and $2,725,706, respectively, related to tax
benefits associated with the exercise of non-qualified stock options. In
addition, during each of the first halves ended August 5, 2001 and July 30,
2000, the Company recorded an increase to additional paid-in capital of $290,155
related to the issuance of restricted stock to satisfy certain deferred
compensation liabilities.


                             See accompanying notes

                                        5
<PAGE>   6

                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

NOTE 1 - BASIS OF PRESENTATION

     The accompanying consolidated financial statements are unaudited except for
the February 4, 2001 balance sheet. These statements have been prepared in
accordance with generally accepted accounting principles for interim financial
information and with the instructions to Form 10-Q and Rule 10-01 of Regulation
S-X. Accordingly, they do not include all of the information and footnotes
required by generally accepted accounting principles for complete financial
statements. The consolidated financial statements include the accounts of
Pacific Sunwear of California, Inc. and its wholly owned subsidiaries (the
"Company"). All significant inter-company transactions have been eliminated in
consolidation.

     The Company's fiscal year is the 52- or 53-week period, which ends on the
Sunday closest to the end of January. "Fiscal 2001" is a 52-week period that
ends February 3, 2002. "Fiscal 2000" was a 53-week period that ended on February
4, 2001.

     In the opinion of management, all adjustments consisting only of normal
recurring entries necessary for a fair presentation have been included. The
preparation of the consolidated financial statements in conformity with
generally accepted accounting principles necessarily requires management to make
estimates and assumptions that affect the reported amounts of assets and
liabilities and disclosure of contingent assets and liabilities at the date of
the consolidated financial statements and reported expenses during the reported
period. Actual results could differ from these estimates. The results of
operations for the second quarter and first half ended August 5, 2001 are not
necessarily indicative of the results that may be expected for the fiscal year
ending February 3, 2002. For further information, refer to the financial
statements and notes thereto as of and for the years ended February 4, 2001,
January 30, 2000 and January 31, 1999.

NOTE 2 - CASH AND CASH EQUIVALENTS

     Cash and cash equivalents include cash on hand and marketable securities
with original maturities of three months or less.

NOTE 3 - DEFERRED COMPENSATION AND OTHER ASSETS

     Deferred compensation and other assets consist of the following:

<TABLE>
<CAPTION>
                                        AUGUST 5,        FEBRUARY 4,
                                          2001              2001
                                       ----------        ----------
<S>                                    <C>               <C>
          Deferred compensation        $7,238,735        $6,994,045
          Other assets                    236,925           275,682
                                       ----------        ----------
                                       $7,475,660        $7,269,727
                                       ==========        ==========
</TABLE>

NOTE 4 - SHORT-TERM BORROWINGS

     The Company has a total credit facility of $55.0 million with a bank, which
provides for a $30.0 million line of credit (the "Credit Line") to be used for
cash advances, commercial letters of credit and shipside bonds, and an
additional $25.0 million line of credit (the "Construction Facility") that can
be used to finance the construction of the Company's new corporate office and
distribution center. The Credit Line expires March 31, 2004. Upon completion of
the new facilities, the Company can, at its option, convert any outstanding
borrowings under the Construction Facility to a term loan. Interest on each of
the credit facilities is payable monthly at the bank's prime rate (6.75% at
August 5, 2001) or at optional interest rates that are primarily dependant upon
the London Inter-bank Offered Rates for the time period chosen. The Company's
weighted average interest rate on its outstanding borrowings was 5.9% at August
5, 2001. At August 5, 2001, the Company had $11,075,000 outstanding under the
Credit Line and $9,000,000 outstanding under the Construction Facility. The
credit facility subjects the Company


                                        6
<PAGE>   7

to various restrictive covenants, including maintenance of certain financial
ratios, and prohibits payment of cash dividends on common stock. At August 5,
2001, the Company was in compliance with all of its covenants.

NOTE 5 - ACCRUED LIABILITIES

     Accrued liabilities consist of the following:

<TABLE>
<CAPTION>
                                                                     AUGUST 5,         FEBRUARY 4,
                                                                       2001               2001
                                                                    -----------        -----------
<S>                                                                 <C>                <C>

     Accrued compensation and benefits                              $ 4,676,852        $ 3,816,279
     Sales tax payable                                                2,781,528          1,284,465
     Accrued gift certificates and store merchandise credits          2,042,326          2,997,512
     Accrued employee medical plan expenses                           1,110,986            514,880
     Accrued freight costs                                            1,017,457            544,144
     Reserve for store expansion/relocation and closing                 637,608          1,489,943
     Other accrued liabilities                                        2,959,377          2,604,196
                                                                    -----------        -----------
                                                                    $15,226,134        $13,251,419
                                                                    ===========        ===========
</TABLE>

NOTE 6 - FEDERAL AND STATE INCOME TAX EXPENSE

     The combined federal and state income tax expense was calculated using
estimated effective annual tax rates.

NOTE 7 - NET INCOME PER SHARE, BASIC AND DILUTED

     The following table summarizes the computation of EPS:

<TABLE>
<CAPTION>

SECOND QUARTER ENDED:                               AUGUST 5, 2001                             JULY 30, 2000
                                       --------------------------------------      ---------------------------------------
                                                                    PER SHARE                                    PER SHARE
                                       NET INCOME       SHARES       AMOUNT        NET INCOME        SHARES       AMOUNT
                                       ----------     ----------    ---------      -----------     ----------    ---------
<S>                                    <C>            <C>           <C>            <C>             <C>           <C>
BASIC EPS:

                                       $3,544,118     32,719,399      $0.11        $ 7,370,730     31,760,227      $0.23

DILUTED EPS:
Effect of dilutive stock options                         382,416                                      556,422
                                       ----------     ----------      -----        -----------     ----------      -----
                                       $3,544,118     33,101,815      $0.11        $ 7,370,730     32,316,649      $0.23
                                       ==========     ==========      =====        ===========     ==========      =====


FIRST HALF ENDED:                                  AUGUST 5, 2001                              JULY 30, 2000
                                       --------------------------------------      ---------------------------------------
                                                                    PER SHARE                                    PER SHARE
                                       NET INCOME       SHARES       AMOUNT        NET INCOME        SHARES       AMOUNT
                                       ----------     ----------    ---------      -----------     ----------    ---------
<S>                                    <C>            <C>           <C>            <C>             <C>           <C>

BASIC EPS:

                                       $4,523,556     32,619,110      $0.14        $13,175,762     31,651,616      $0.42
DILUTED EPS:
Effect of dilutive stock options                         516,838                                      799,601
                                       ----------     ----------      -----        -----------     ----------      -----
                                       $4,523,556     33,135,948      $0.14        $13,175,762     32,451,217      $0.41
                                       ==========     ==========      =====        ===========     ==========      =====
</TABLE>

     Options to purchase 1,033,198 and 1,041,988 shares of common stock in the
second quarter of fiscal 2001 and fiscal 2000, respectively, and 443,326 and
244,159 in the first half of fiscal 2001 and fiscal 2000, respectively, were not
included in the computation of diluted earnings per common share because the
option exercise price was greater than the average market price of the common
stock.

NOTE 8 - ONE-TIME NON-CASH CHARGE

     During the first quarter of fiscal 2001, the Company recorded a one-time
non-cash charge of $2.5 million after tax ($4.2 million pre-tax), or $.08 per
basic and diluted share, related to the disposal of most of the existing
materials handling equipment in its current distribution center as part of its
relocation to a new distribution facility in Anaheim, California scheduled for
January 2002. The $4.2 million pre-tax charge is included in selling, general
and administrative expenses.


                                       7

<PAGE>   8

                MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                CONDITION AND RESULTS OF CONSOLIDATED OPERATIONS

RESULTS OF OPERATIONS

The thirteen weeks ended August 5, 2001(second quarter) as compared to the
thirteen weeks ended July 30, 2000 (second quarter)

     Net Sales

     Net sales increased to $156.5 million for the second quarter of fiscal 2001
from $132.0 million for the second quarter of fiscal 2000, an increase of $24.5
million, or 18.6%. Of this $24.5 million increase, $13.2 million was
attributable to net sales generated by 89 new stores opened in fiscal 2001 and
not yet included in the comparable store base, $11.2 million was attributable to
net sales generated by 55 new stores opened in fiscal 2000 and not yet included
in the comparable store base and $1.9 million was attributable to other
non-comparable store net sales. An additional $7.9 million increase in net sales
was attributable to a one week shift in the fiscal calendar. Fiscal 2000 was a
fifty-three week period ended February 4, 2001 and fiscal 2001 will be a
fifty-two week period ending February 3, 2002. The extra week in the prior
fiscal year caused a change in the measurement period used in making
period-to-period comparisons. Offsetting these increases was a $9.2 million
decrease attributable to a 7.3% decrease in comparable store net sales in the
second quarter of fiscal 2001 and a $.5 million decrease in net sales
attributable to the closing of one and three stores during fiscal 2001 and
fiscal 2000, respectively. The decrease in comparable store net sales was
primarily attributable to decreases in net sales of young men's merchandise and,
to a lesser extent, girls' merchandise, offset by increases in net sales of
accessories and footwear. Other non-comparable store net sales consist of sales
from stores that have been expanded or relocated and not yet included in the
comparable store base as well as merchandise sold over the internet. Stores are
deemed comparable stores on the first day of the first month following the
one-year anniversary of their opening or expansion/relocation. Retail prices of
the Company's merchandise remained relatively unchanged in the second quarter of
fiscal 2001 compared to the second quarter of fiscal 2000 and had no significant
impact on the net sales increase for the second quarter of fiscal 2001.

     Gross Margin

     Gross margin, after buying, distribution and occupancy costs, increased to
$48.2 million for the second quarter of fiscal 2001 from $43.8 million for the
second quarter of fiscal 2000, an increase of $4.4 million, or 10.0%. As a
percentage of net sales, gross margin was 30.8% for the second quarter of fiscal
2001 compared to 33.2% for the second quarter of fiscal 2000. Of this 2.4%
decrease, occupancy costs increased 1.2% as a percentage of net sales compared
to the second quarter of fiscal 2000, which was primarily related to lower
comparable store net sales in the second quarter of fiscal 2001. In addition,
net merchandise margins decreased 1.2% as a percentage of net sales, primarily
due to a higher markdown rate.

     Selling, General and Administrative Expenses

     Selling, general and administrative expenses increased to $42.4 million for
the second quarter of fiscal 2001 from $31.9 million for the second quarter of
fiscal 2000, an increase of $10.5 million, or 32.9%. As a percentage of net
sales, these expenses increased to 27.1% from 24.2%. Of this 2.9% net increase
as a percentage of net sales, 1.9% was due to an increase in store payroll and
other selling expenses, primarily as a result of lower comparable store net
sales in the second quarter of fiscal 2001. In addition, advertising costs
increased 1.0% as a percentage of net sales, primarily as a result of increased
television advertising in comparison to the second quarter of fiscal 2000.

     Income Tax Expense

     Income tax expense was $2.2 million for the second quarter of fiscal 2001
compared to $4.7 million for the second quarter of fiscal 2000. The effective
income tax rate was 38.4% for the second quarter of fiscal 2001 as compared to
38.8% for the second quarter of fiscal 2000.


                                       8

<PAGE>   9

The twenty-six weeks ended August 5, 2001(first half) as compared to the
twenty-six weeks ended July 30, 2000 (first half)

     Net Sales

     Net sales increased to $294.2 million for the first half of fiscal 2001
from $244.5 million for the first half of fiscal 2000, an increase of $49.7
million, or 20.3%. Of this $49.7 million increase, $31.8 million was
attributable to net sales generated by 55 new stores opened in fiscal 2000 and
not yet included in the comparable store base, $17.0 million was attributable to
net sales generated by 89 new stores opened in fiscal 2001 and not yet included
in the comparable store base and $4.1 million was attributable to other
non-comparable store net sales. An additional $10.2 million increase in net
sales was attributable to a one week shift in the fiscal calendar. Fiscal 2000
was a fifty-three week period ended February 4, 2001 and fiscal 2001 will be a
fifty-two week period ending February 3, 2002. The extra week in the prior
fiscal year caused a change in the measurement period used in making
period-to-period comparisons. Offsetting these increases was a $12.5 million
decrease attributable to a 5.5% decrease in comparable store net sales in the
first half of fiscal 2001 and a $0.9 million decrease in net sales attributable
to the closing of one and three stores during fiscal 2001 and fiscal 2000,
respectively. The decrease in comparable store net sales was primarily
attributable to decreases in net sales of young men's merchandise and, to a
lesser extent, girls' merchandise, offset by increases in net sales of
accessories and footwear. Other non-comparable store net sales consist of sales
from stores that have been expanded or relocated and not yet included in the
comparable store base as well as merchandise sold over the internet. Stores are
deemed comparable stores on the first day of the first month following the
one-year anniversary of their opening or expansion/relocation. Retail prices of
the Company's merchandise remained relatively unchanged in the first half of
fiscal 2001 compared to the first half of fiscal 2000 and had no significant
impact on the net sales increase for the first half of fiscal 2001.

     Gross Margin

     Gross margin, after buying, distribution and occupancy costs, increased to
$90.1 million for the first half of fiscal 2001 from $81.7 million for the first
half of fiscal 2000, an increase of $8.4 million, or 10.3%. As a percentage of
net sales, gross margin was 30.6% for the first half of fiscal 2001 compared to
33.4% for the first half of fiscal 2000. Of this 2.8% decrease, occupancy costs
increased 1.4% as a percentage of net sales compared to the first half of fiscal
2000, which was primarily related to lower comparable store net sales in the
first half of fiscal 2001. In addition, net merchandise margins decreased 1.2%
as a percentage of net sales, primarily due to a higher markdown rate, and
buying costs increased .2%.

     Selling, General and Administrative Expenses

     Selling, general and administrative expenses increased to $83.0 million for
the first half of fiscal 2001 from $60.6 million for the first half of fiscal
2000, an increase of $22.4 million, or 37.0%. As a percentage of net sales,
these expenses increased to 28.2% from 24.8%. Of this 3.4% net increase as a
percentage of net sales, 1.4% was due to a one-time non-cash after tax charge of
$2.5 million related to the disposal of most of the existing materials handling
equipment as part of the Company's relocation to a new distribution facility
scheduled for January 2002. Of the remaining net increase of 2.0%, 1.8% was due
to an increase in store payroll and other selling expenses as a percentage of
net sales, primarily as a result of lower comparable store net sales in the
first half of fiscal 2001. In addition, advertising costs increased .2% as a
percentage of net sales.

     Income Tax Expense

     Income tax expense was $2.8 million for the first half of fiscal 2001
compared to $8.4 million for the first half of fiscal 2000. The effective income
tax rate was 38.4% for the first half of fiscal 2001 as compared to 38.8% for
the first half of fiscal 2000.


                                        9

<PAGE>   10

LIQUIDITY AND CAPITAL RESOURCES

     The Company has financed its operations from internally generated cash
flow, short-term borrowings and equity financing. The Company's primary capital
requirements have been for the construction of new stores, remodeling,
expansion, or relocation of selected stores and financing of inventories. In
December 2000, the Company purchased an undeveloped 19-acre parcel of land in
close proximity to its current corporate office and distribution center for
$12.2 million. The Company has begun construction of a new corporate office and
distribution center on this property and anticipates they will be ready for
occupancy in January 2002. The Company believes the new facilities will be
capable of servicing at least 1,200 stores. The Company intends to sublease its
existing corporate offices and distribution center for the remainder of the
lease.

     Net cash used in operating activities for the first half of fiscal 2001 was
$9.9 million as compared to net cash provided of $4.6 million for the first half
of fiscal 2000. This $14.5 million increase in cash used was primarily
attributable to an increase in inventories net of accounts payable of $18.7
million and a decrease in net income of $8.7 million. These were offset by a
$4.2 million one-time non-cash charge for the disposal of most of the existing
materials handling equipment in the Company's current distribution center, an
increase in depreciation and amortization of $3.8 million, an increase in
accrued liabilities of $2.2 million, a decrease in prepaid expenses of $1.4
million, an increase in accrued income taxes and deferred income taxes of $1.2
million, and other items netting to an increase of $.1 million. Working capital
at August 5, 2001 decreased $2.4 million to $77.4 million compared to $79.8
million at February 4, 2001. Inventories at August 5, 2001 were $124.3 million
compared to $82.7 million at February 4, 2001, an increase of $41.6 million.
This increase was primarily related to opening 89 new stores and
expanding/relocating 25 stores in the first half of fiscal 2001 with in excess
of 50% larger average square footage than their previous locations. The
Company's average store inventories vary throughout the year and increase in
advance of the peak selling periods of spring break, back-to-school and
Christmas.

     Net cash used in investing activities was $38.9 million for property and
equipment for the first half of fiscal 2001 compared to $25.6 million for
property and equipment for the first half of fiscal 2000. Of the $38.9 million
of net cash used for investment in property and equipment in the first half of
fiscal 2001, $25.8 million was used for new and existing stores, $11.5 million
was used for costs related to the construction of the new corporate office and
distribution center and $1.6 million was used for other capital expenditures
including computer hardware and software.

     Net cash provided by financing activities was $23.5 million for the first
half of fiscal 2001 as compared to $1.9 million for the first half of 2000, an
increase of $21.6 million. This $21.6 million increase in cash provided was
primarily due to $20.1 million in short-term borrowings under the Company's
credit facility and an increase of $1.8 million of proceeds received from the
exercise of stock options. These increases were offset by $.3 million of
principal payments under capital lease obligations.

     The Company has a total credit facility of $55.0 million with a bank, which
provides for a $30.0 million line of credit (the "Credit Line") to be used for
cash advances, commercial letters of credit and shipside bonds, and an
additional $25.0 million line of credit (the "Construction Facility") that can
be used to finance the construction of the Company's new corporate office and
distribution center. The Credit Line expires March 31, 2004. Upon completion of
the new facilities, the Company can, at its option, convert any outstanding
borrowings under the Construction Facility to a term loan. Interest on each of
the credit facilities is payable monthly at the bank's prime rate (6.75% at
August 5, 2001) or at optional interest rates that are primarily dependant upon
the London Inter-bank Offered Rates for the time period chosen. The Company's
weighted average interest rate on its outstanding borrowings was 5.9% at August
5, 2001. At August 5, 2001, the Company had $11.1 million outstanding under the
Credit Line and $9.0 million outstanding under the Construction Facility.
Additionally, the Company had $10.0 million in letters of credit outstanding at
August 5, 2001. The credit facility subjects the Company to various restrictive
covenants, including maintenance of certain financial ratios, and prohibits
payment of cash dividends on common stock. At August 5, 2001, the Company was in
compliance with all of its covenants.

     The Company plans to open approximately 46 new stores, of which
approximately 29 will be PacSun stores, approximately 6 will be PacSun Outlet
stores and approximately 11 will be d.e.m.o. stores during the remainder of
fiscal 2001. The Company also plans to expand or relocate approximately 11
existing smaller stores


                                       10

<PAGE>   11

during the remainder of fiscal 2001. The Company estimates that capital
expenditures during the remainder of fiscal 2001 will be approximately $55
million, of which approximately $20 million will be for opening, expanding, and
relocating stores, approximately $31 million will be to construct a new
corporate office and distribution center and install a materials handling
system, and approximately $4 million will be used for other capital
expenditures, including computer hardware and software. The Company plans to
open approximately 75 net new stores during the year ended February 2, 2003
("fiscal 2002").

     The Company reviews the operating performance of its stores on an ongoing
basis to determine which stores, if any, to expand, relocate or close. The
Company closed three stores in fiscal 2000 and anticipates closing approximately
five stores in fiscal 2001.

     Management believes that the Company's working capital, credit facility and
cash flows from operating activities will be sufficient to meet the Company's
operating and capital expenditure requirements through the end of fiscal 2001.

INFLATION

     The Company does not believe that inflation has had a material effect on
the results of operations in the recent past. There can be no assurance that the
Company's business will not be affected by inflation in the future.

NEW ACCOUNTING PRONOUNCEMENTS

     In July 2001, the Financial Accounting Standards Board issued Statement No.
141 ("SFAS No. 141"), "Business Combinations," and Statement No. 142 ("SFAS No.
142"), "Goodwill and Other Intangible Assets." SFAS No. 141 prospectively
prohibits the pooling of interest method of accounting for business combinations
initiated after June 30, 2001. Effective for fiscal years beginning on or after
January 1, 2002, SFAS No. 142 requires companies to cease amortizing goodwill
that existed at June 30, 2001, and, therefore, the Company's amortization of
existing goodwill will cease on February 3, 2001. In addition, under SFAS No.
142, any goodwill resulting from acquisitions completed after June 30, 2001 will
not be amortized. SFAS No. 142 also includes requirements to test goodwill and
indefinite lived intangible assets for impairment beginning in fiscal 2002.
Currently, the Company is not a party to any agreement or understanding with
respect to any prospective acquisition and does not anticipate any impairment on
its existing goodwill. In the absence of any impairment issues, the Company
expects the impact of these statements to increase pre-tax income by
approximately $.3 million per year through 2022.

SEASONALITY AND QUARTERLY RESULTS

     The Company's business is seasonal by nature, with the Christmas and
back-to-school periods historically accounting for the largest percentage of
annual net sales. The Company's first quarter historically accounts for the
smallest percentage of annual net sales. In each of fiscal 2000 and fiscal 1999,
excluding sales generated by new and relocated/expanded stores, the Christmas
and back-to-school periods together accounted for approximately 33% of the
Company's annual net sales and a higher percentage of the Company's operating
income. In fiscal 2000, excluding net sales generated by new and
relocated/expanded stores, approximately 46% of the Company's annual net sales
occurred in the first half of the fiscal year and 54% in the second half. The
Company's quarterly results of operations may also fluctuate significantly as a
result of a variety of factors, including the timing of store openings; the
amount of revenue contributed by new stores; the timing and level of markdowns;
the timing of store closings, expansions and relocations; competitive factors;
and general economic conditions.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS AND RISK FACTORS

     This report on Form 10-Q contains "forward-looking statements" within the
meaning of Sections 27A of the Securities Act of 1933 and Section 21E of the
Securities Exchange Act of 1934, and the Company intends that such
forward-looking statements be subject to the safe harbors created thereby. The
Company is hereby providing cautionary statements identifying important factors
that could cause the Company's actual results to differ materially from those
projected in forward-looking statements of the Company herein. Any statements
that express, or involve discussions as to expectations, beliefs, plans,
objectives, assumptions, future events or


                                       11
<PAGE>   12

performance (often, but not always through the use of words or phrases such as
"will result," "expects to," "will continue," "anticipates," "plans," "intends,"
"estimated," "projects" and "outlook") are not historical facts and may be
forward-looking and, accordingly, such statements involve estimates, assumptions
and uncertainties which could cause actual results to differ materially from
those expressed in the forward-looking statements. Such uncertainties include,
among others, the following factors:

     MERCHANDISING/FASHION SENSITIVITY. The Company's success is largely
dependent upon its ability to gauge the fashion tastes of its customers and to
provide merchandise that satisfies customer demand in a timely manner. The
Company's failure to anticipate, identify or react appropriately in a timely
manner to changes in fashion trends could have a material adverse effect on the
Company's business, financial condition and results of operations. Misjudgments
or unanticipated fashion misjudgments could have a material adverse effect on
the Company's image with its customers.

     PRIVATE LABEL MERCHANDISE. Sales from private label merchandise accounted
for approximately 36% of net sales in each of fiscal 2000 and fiscal 1999. The
Company may increase the percentage of net sales in private label merchandise in
the future, although there can be no assurance that the Company will be able to
achieve increases in private label merchandise sales as a percentage of net
sales. Because the Company's private label merchandise generally carries higher
merchandise margins than its other merchandise, the Company's failure to
anticipate, identify and react in a timely manner to fashion trends with its
private label merchandise, particularly if the percentage of net sales derived
from private label merchandise increases, may have a material adverse affect on
the Company's business, financial condition and results of operations.

     FLUCTUATIONS IN COMPARABLE STORE NET SALES RESULTS. The Company's
comparable store net sales results have fluctuated significantly in the past, on
a monthly, quarterly and annual basis, and are expected to continue to fluctuate
in the future. A variety of factors affect the Company's comparable store net
sales results, including changes in fashion trends, changes in the Company's
merchandise mix, calendar shifts of holiday periods, actions by competitors,
weather conditions and general economic conditions. The Company's comparable
store net sales results for any particular fiscal month, fiscal quarter or
fiscal year in the future may decrease. As a result of these or other factors
the Company's future comparable store net sales results are likely to have a
significant effect on the market price of the Company's common stock.

     EXPANSION AND MANAGEMENT OF GROWTH. PacSun's continued growth depends to a
significant degree on its ability to open and operate stores on a profitable
basis and on management's ability to manage the Company's planned expansion.
During the remainder of fiscal 2001, the Company plans to open approximately 46
new stores, of which approximately 29 will be PacSun stores, approximately 6
will be PacSun Outlet stores and approximately 11 will be d.e.m.o. stores. In
addition, the Company plans to open approximately 75 net new stores during
fiscal 2002. The Company's planned expansion is dependant upon a number of
factors, including the ability of the Company to locate and obtain favorable
store sites, negotiate acceptable lease terms, obtain adequate supplies of
merchandise and hire and train qualified management level and other employees.
Factors beyond the Company's control may also affect the Company's ability to
expand, including general economic and business conditions affecting consumer
spending. There can be no assurance that the Company will achieve its planned
expansion or that such expansion will be profitable. As the Company's operations
grow, there could be increasing strain on the Company's resources, and the
Company could experience difficulties relating to a variety of operational
matters, including hiring, training and managing an increasing number of
employees, having sufficient working capital, bank line of credit and cash flow
from operating activities for the Company's future operating and capital
requirements, obtaining sufficient quantities of merchandise from its preferred
vendors, obtaining sufficient materials and contract manufacturers to produce
its private brand products and enhancing its distribution, financial and
operating systems. There can be no assurance that the Company will be able to
manage its growth effectively. Any failure to manage growth could have a
material adverse effect on the Company's business, financial condition and
results of operations.

     RELIANCE ON KEY PERSONNEL. The continued success of the Company is
dependant to a significant degree upon the services of its key personnel,
particularly its executive officers. The loss of the services of any member of
senior management could have a material adverse effect on the Company's
business, financial condition and results of operations. The Company's success
in the future will also be dependent upon the Company's ability to attract and
retain qualified personnel. The Company's inability to attract and retain
qualified personnel in the future could have a material adverse effect on the
Company's business, financial condition and results of operations.


                                       12
<PAGE>   13

     DEPENDENCE ON SINGLE DISTRIBUTION FACILITY AND PLANNED RELOCATION. The
Company's distribution functions for all of its stores and for Internet sales
are handled from a single, leased facility in Anaheim, California. The Company
is currently constructing a new corporate office and distribution center in
Anaheim, California, and anticipates they will be ready for occupancy in January
2002, to handle distribution functions for all of its stores as well as
shipments of merchandise sold over the Internet. Any significant interruption in
the operation of the distribution facility due to natural disasters, accidents,
system failures, relocation difficulties or other unforeseen causes would have a
material adverse effect on the Company's business, financial condition and
results of operations. There can be no assurance that the Company's new
corporate office and distribution center will be completed by January 2002, or
that it will be adequate to support the Company's future growth. The Company
will incur significant costs and expenditures to build its new facilities, which
could have an impact on the Company's financial condition and results of
operations. The actual cost of completing these facilities may be greater than
the Company's current estimates.

     STORES IN THE D.E.M.O. FORMAT. The Company opened its first d.e.m.o. store
in April of fiscal 1998 and as of August 5, 2001 operated 91 d.e.m.o. stores.
There can be no assurance that the Company's d.e.m.o. stores will achieve sales
and profitability levels that justify the Company's investment in this new
retail format. Expansion of the d.e.m.o. format involves risks that could have a
material adverse effect on the Company, including (i) diversion of management's
attention from the Company's core business, (ii) difficulties with hiring,
retention and training of key personnel for the d.e.m.o. stores, (iii) risks
associated with new vendors and (iv) difficulties with locating and obtaining
favorable store sites and negotiating acceptable lease terms.

     INTERNET SALES. The Company began selling merchandise over the internet in
June 1999. The Company's internet operations are subject to numerous risks,
including unanticipated operating problems, reliance on third party computer
hardware and software providers, system failures and the need to invest in
additional computer systems. There can be no assurance that the internet
operations will achieve sales and profitability levels that justify the
Company's investment therein. The internet operations also involve other risks
that could have a material adverse effect on the Company, including (i) the
failure to reach profitability within the foreseeable future, (ii) difficulties
with hiring, retention and training of key personnel to conduct the Company's
internet operations, (iii) diversion of sales from PacSun stores, (iv) rapid
technological change, (v) liability for online content and (vi) risks related to
the failure of the computer systems that operate the web site and its related
support systems, including computer viruses, telecommunication failures and
electronic break-ins and similar disruptions. In addition, the internet
operations involve risks which are beyond the Company's control that could have
a material adverse effect on the Company, including (i) price competition
involving the items the Company intends to sell, (ii) the entry of the Company's
vendors into the internet business, in direct competition with the Company,
(iii) the level of merchandise returns experienced by the Company, (iv)
governmental regulation, (v) online security breaches, (vi) credit card fraud
and (vii) competition and general economic conditions and economic conditions
specific to the internet, online commerce and the apparel industry.

     VOLATILITY OF STOCK PRICE. The market price of the Company's common stock
has fluctuated substantially in the past and there can be no assurance that the
market price of the common stock will not continue to fluctuate significantly.
Future announcements or management discussions concerning the Company or its
competitors, internet sales results, d.e.m.o. sales and profitability results,
quarterly variations in operating results or comparable store net sales, changes
in earnings estimates by analysts or changes in accounting policies, among other
factors, could cause the market price of the common stock to fluctuate
substantially. In addition, stock markets have experienced extreme price and
volume volatility in recent years. This volatility has had a substantial effect
on the market prices of securities of many smaller public companies for reasons
frequently unrelated to the operating performance of the specific companies.

                                  *************


                                       13

<PAGE>   14

     The Company cautions that the risk factors described above could cause
actual results or outcomes to differ materially from those expressed in any
forward-looking statements of the Company made by or on behalf of the Company.
Further, management cannot assess the impact of each such factor on the
Company's business or the extent to which any factor, or combination of factors,
may cause actual results to differ materially from those contained in any
forward-looking statements.

     QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

     To the extent the Company borrowed under its credit facility, the Company
would be exposed to market risk related to changes in interest rates. At August
5, 2001, $20.1 million in borrowings were outstanding under the Company's credit
facility. A discussion of the Company's accounting policies for financial
instruments and further disclosures relating to financial instruments is
included in the Summary of Significant Accounting Policies and Nature of
Business in the Notes to Consolidated Financial Statements in the Company's Form
10-K for the year ended February 4, 2001. The Company is not a party with
respect to derivative financial instruments.


                                       14

<PAGE>   15

                            PART II-OTHER INFORMATION

Item 1 - Legal Proceedings - Not Applicable

Item 2 - Changes in Securities and Use of Proceeds - Not Applicable

Item 3 - Defaults Upon Senior Securities - Not Applicable

Item 4 - Submission of Matters to a Vote of Security Holders

(a) The 2001 Annual Meeting of Shareholders of the Company was held on May 30,
    2001.

(b) At the 2001 Annual Meeting, Greg H. Weaver, Julius Jensen III, Pearson C.
    Cummin III, Peter L. Harris and Sally Frame Kasaks were elected as Directors
    of the Company for a one-year term ending in 2002.

Voting at the 2001 Annual Meeting for the election of directors was as set forth
below. Each of the nominees identified below was elected a director.

<TABLE>
<CAPTION>
                                          VOTES CAST                  VOTES
       NAME                                  FOR                     WITHHELD
       ----                               ----------                 --------
<S>                                       <C>                        <C>
Greg H. Weaver                            28,328,039                  11,605
Julius Jensen III                         28,328,040                  11,604
Pearson C. Cummin III                     28,328,040                  11,604
Peter L. Harris                           28,328,040                  11,604
Sally Frame Kasaks                        28,328,040                  11,604
</TABLE>

(c) In addition to the election of directors, the shareholders voted on and
    approved an amendment to the Company's 1999 Stock Award Plan (the "Plan")
    that increased the number of shares authorized to be issued under the Plan
    by an additional 2,000,000 shares and increased certain other share limits
    under the Plan.

Voting at the 2001 Annual Meeting for the amendment to the 1999 Stock Award Plan
was as set forth below.

<TABLE>
<CAPTION>
          VOTES CAST        VOTES CAST          VOTES            BROKER
             FOR             AGAINST          ABSTAINING        NON-VOTES
          ----------        ----------        ----------        ---------
<S>                         <C>               <C>               <C>
          23,724,326        2,568,733           19,780          2,026,805
</TABLE>

Item 5 - Other Information - Not Applicable

Item 6 - Exhibits and Reports on Form 8-K

     (a)  Exhibits:

          10.1 -- Second Amendment to Business Loan Agreement, dated as of
                  August 1, 2001, between the Company and Bank of America N.A.

     (b)  Reports on Form 8-K:

          No reports were filed on form 8-K during the quarter for which this
          report is filed.


                                       15

<PAGE>   16

                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                             Pacific Sunwear of California, Inc.
                                             (Registrant)


Date: September 11, 2001                     /s/ GREG H. WEAVER
                                             -----------------------------------
                                                 Greg H. Weaver
                                                 Chairman of the Board
                                                 and Chief Executive Officer


Date: September 11, 2001                     /s/ CARL W. WOMACK
                                             -----------------------------------
                                                 Carl W. Womack
                                                 Senior Vice President, Chief
                                                 Financial Officer and Secretary


                                       16

<PAGE>   17

                                 EXHIBIT INDEX

Exhibit
Number                                  Description
------                                  -----------

  10.1           Second Amendment to Business Loan Agreement, dated as of August
                 1, 2001, between the Company and Bank of America N.A.