<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 MAY 2, 1999

                                       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 May 18, 1999 was 20,583,899.


<PAGE>   2
                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                                    FORM 10-Q
                        FOR THE QUARTER ENDED MAY 2, 1999

                                      INDEX


<TABLE>
<CAPTION>
PART I.    FINANCIAL INFORMATION                                                                              PAGE
<S>                                                                                                          <C>
Item 1.    Consolidated Financial Statements:
           Consolidated Balance Sheets as of May 2, 1999 (unaudited)
             and January 31, 1999................................................................................3
           Consolidated Statements of Income and Comprehensive Income  (unaudited)
             for the thirteen weeks ended May 2, 1999 and May 3, 1998............................................4
           Consolidated Statements of Cash Flows (unaudited) for the thirteen weeks
             ended May 2, 1999 and May 3, 1998...................................................................5
           Notes to Consolidated Financial Statements..........................................................6-7

Item 2.    Management's Discussion and Analysis of Financial Condition
             and Results of Operations........................................................................8-13

Item 3.    Quantitative and Qualitative Disclosures About Market Risk...........................................13

PART II.   OTHER INFORMATION
Item 1.    Legal Proceedings....................................................................................14
Item 2.    Changes in Securities and Use of Proceeds............................................................14
Item 3.    Defaults Upon Senior Securities......................................................................14
Item 4.    Submission of Matters to a Vote of Security Holders..................................................14
Item 5.    Other Information....................................................................................14
Item 6.    Exhibits and Reports on Form 8-K.....................................................................14

           SIGNATURE PAGE.......................................................................................15
</TABLE>


                                       2
<PAGE>   3
                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                           CONSOLIDATED BALANCE SHEETS


<TABLE>
<CAPTION>
                                     ASSETS
                                                                                               MAY 2,                JANUARY 31,
                                                                                                1999                    1999
                                                                                            -------------           -------------
<S>                                                                                         <C>                     <C>
CURRENT ASSETS:                                                                              (Unaudited)
  Cash and cash equivalents (Note 2)                                                        $  11,253,028           $  19,031,738
  Accounts receivable                                                                           2,415,226                 899,179
  Merchandise inventories                                                                      46,444,821              42,469,829
  Prepaid expenses, includes $3,775,556 and $3,620,435 of prepaid rent, respectively            5,889,245               5,044,941
  Prepaid income tax                                                                                   --                 713,402
  Deferred taxes                                                                                1,944,275               1,944,275
                                                                                            -------------           -------------
    Total current assets                                                                       67,946,595              70,103,364
PROPERTY AND EQUIPMENT:
  Leasehold improvements                                                                       53,409,402              47,877,157
  Furniture, fixtures and equipment                                                            50,112,807              45,819,759
                                                                                            -------------           -------------
                                                                                              103,522,209              93,696,916
  Less accumulated depreciation and amortization                                              (28,857,495)            (26,773,496)
                                                                                            -------------           -------------
    Net property and equipment                                                                 74,664,714              66,923,420
OTHER ASSETS:
  Goodwill, net of accumulated amortization of $837,651 and $758,180, respectively              7,526,092               7,605,563
  Deferred compensation and other assets (Note 6)                                               3,698,592               3,142,504
                                                                                            -------------           -------------
    Total other assets                                                                         11,224,684              10,748,067
                                                                                            -------------           -------------
              Total assets                                                                  $ 153,835,993           $ 147,774,851
                                                                                            =============           =============

                      LIABILITIES AND SHAREHOLDERS' EQUITY

CURRENT LIABILITIES:
  Accounts payable                                                                          $  13,303,326           $  13,867,906
  Accrued liabilities (Note 5)                                                                  7,720,482               8,690,783
  Income taxes payable                                                                            446,092                      --
                                                                                            -------------           -------------
    Total current liabilities                                                                  21,469,900              22,558,689
DEFERRED COMPENSATION                                                                           3,112,838               2,826,531
OTHER LONG-TERM LIABILITIES                                                                        28,316                  28,316
DEFERRED RENT                                                                                   4,900,803               4,689,772
DEFERRED TAXES                                                                                    974,522                 974,522


SHAREHOLDERS' EQUITY:
  Preferred stock, par value $.01; authorized, 5,000,000; none issued and outstanding
  Common stock, par value $.01; authorized 50,625,000 shares; issued and
     outstanding, 20,569,947 and 20,433,852 shares, respectively                                  205,699                 204,339
  Additional paid-in capital                                                                   62,510,539              59,902,375
  Retained earnings                                                                            60,633,376              56,590,307
                                                                                            -------------           -------------
    Total shareholders' equity                                                                123,349,614             116,697,021
                                                                                            -------------           -------------
                  Total liabilities and shareholders' equity                                $ 153,835,993           $ 147,774,851
                                                                                            =============           =============
</TABLE>


                             See accompanying notes


                                       3
<PAGE>   4
                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                      CONSOLIDATED STATEMENTS OF INCOME AND
                              COMPREHENSIVE INCOME
                                   (Unaudited)


<TABLE>
<CAPTION>
                                                        FOR THE THIRTEEN WEEKS ENDED
                                                      --------------------------------
                                                      MAY 2, 1999          MAY 3, 1998
                                                      -----------          -----------
<S>                                                   <C>                  <C>
Net sales                                             $81,442,910          $61,162,250
Cost of goods sold, including buying,
  distribution and occupancy costs                     55,297,787           41,555,214
                                                      -----------          -----------
Gross margin                                           26,145,123           19,607,036
Selling, general and administrative expenses           19,681,292           15,147,526
                                                      -----------          -----------
Operating income                                        6,463,831            4,459,510
Interest income                                           112,238              320,404
                                                      -----------          -----------
Income before income tax expense                        6,576,069            4,779,914
Income tax expense (Note 4)                             2,533,000            1,893,000
                                                      -----------          -----------
Net income                                            $ 4,043,069          $ 2,886,914
                                                      ===========          ===========
Comprehensive income (Note 1)                         $ 4,043,069          $ 2,886,914
                                                      ===========          ===========

Net income per share, basic (Note 3)                  $      0.20          $      0.14
                                                      -----------          -----------

Net income per share, diluted (Note 3)                $      0.19          $      0.13
                                                      -----------          -----------
Weighted average shares outstanding, basic
(Note 3)                                               20,488,049           20,675,355
                                                      ===========          ===========
Weighted average shares outstanding,
diluted (Note 3)                                       21,239,207           21,495,905
                                                      ===========          ===========
</TABLE>


                             See accompanying notes


                                       4
<PAGE>   5
                       PACIFIC SUNWEAR OF CALIFORNIA, INC.

                      CONSOLIDATED STATEMENTS OF CASH FLOWS
                                   (Unaudited)


<TABLE>
<CAPTION>
                                                                         FOR THE THIRTEEN WEEKS ENDED
                                                                     -----------------------------------
                                                                      MAY 2, 1999            MAY 3, 1998
                                                                     ------------           ------------
<S>                                                                  <C>                    <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income                                                           $  4,043,069           $  2,886,914

Adjustments to reconcile net income to net cash provided by
   operating activities:
   Depreciation and amortization                                        3,095,081              2,133,131
   Change in:
     Accounts receivable                                               (1,516,047)              (285,542)
     Merchandise inventories                                           (3,974,992)            (1,714,916)
     Prepaid expenses                                                    (844,304)                36,961
     Deferred compensation and other assets                              (282,282)               502,825
     Accounts payable                                                    (564,580)             1,763,730
     Accrued liabilities                                                 (970,301)            (2,492,835)
     Income taxes and deferred income taxes                             2,472,982               (154,105)
     Deferred rent                                                        211,031                386,761
                                                                     ------------           ------------
        Net cash provided by operating activities                       1,669,657              3,062,924
CASH FLOWS FROM INVESTING ACTIVITIES:
   Short term investment maturities                                            --              9,857,178
   Investment in property and equipment                               (10,744,403)            (9,447,899)
                                                                     ------------           ------------
        Net cash (used in) provided by investing activities           (10,744,403)               409,279
CASH FLOWS FROM FINANCING ACTIVITIES:
   Proceeds from exercise of stock options                              1,296,036                266,960
                                                                     ------------           ------------
        Net cash provided by financing activities                       1,296,036                266,960
                                                                     ------------           ------------
NET (DECREASE) INCREASE IN CASH AND CASH
     EQUIVALENTS:                                                      (7,778,710)             3,739,163
  CASH AND CASH EQUIVALENTS, beginning of period                       19,031,738             14,781,566
                                                                     ------------           ------------
  CASH AND CASH EQUIVALENTS, end of period                           $ 11,253,028           $ 18,520,729
                                                                     ============           ============
SUPPLEMENTAL DISCLOSURES OF CASH FLOW
   INFORMATION:
Cash paid during the period for:
  Interest                                                           $         --           $         --
  Income taxes                                                       $     60,018           $  2,047,105
</TABLE>


Non-cash transaction: During the three months ended May 2, 1999 and May 3, 1998,
the Company recorded an increase to additional paid-in capital of $1,313,488 and
$881,356, respectively, related to tax benefits associated with the exercise of
non-qualified stock options.


                             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 January 31, 1999 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 intercompany 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 1999" is a 52-week period which
ends January 30, 2000.

        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 first quarter ended May 2, 1999 are not necessarily
indicative of the results that may be expected for the fiscal year ending
January 30, 2000. For further information, refer to the financial statements and
notes thereto as of and for the years ended January 31, 1999, February 1, 1998
and February 2, 1997.

        Comprehensive Income -- The Company adopted SFAS No. 130, "Reporting
Comprehensive Income", in the first quarter 1998. SFAS No. 130 establishes
standards for the reporting and display of comprehensive income. Components of
comprehensive income include net earnings (loss), foreign currency translation
adjustments and gains/losses associated with investments available for sale. The
adoption of SFAS No. 130 required no additional disclosure for the Company and
did not have any effect on the Company's financial position or results of
operations.

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 - NET INCOME PER SHARE, BASIC AND DILUTED

        The following table summarizes the computation of EPS:


<TABLE>
<CAPTION>
THIRTEEN WEEKS ENDED:                                MAY 2, 1999                                MAY 3, 1998
                                      ---------------------------------------    --------------------------------------
                                          NET                       PER SHARE        NET                      PER SHARE
                                        INCOME          SHARES       AMOUNT        INCOME          SHARES       AMOUNT
                                      ----------      ----------    ---------    ----------      ----------   ---------
<S>                                   <C>             <C>           <C>          <C>             <C>          <C>
BASIC EPS:
Net Income                            $4,043,069      20,488,049      $0.20      $2,886,914      20,675,355      $0.14
DILUTED EPS:
Effect of dilutive stock options                         751,158                                    820,550
Net Income                            $4,043,069      21,239,207      $0.19      $2,886,914      21,495,905      $0.13
                                      ----------      ----------      -----      ----------      ----------      -----
</TABLE>

        Options to purchase 9,904 and 4,212 shares of common stock in the first
thirteen weeks of fiscal 1999 and the first thirteen weeks of fiscal 1998,
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.


                                       6
<PAGE>   7
        Stock Split - On June 8, 1998, the Company effected a three-for-two
stock split. Earnings per share and share outstanding amounts have been restated
to give retroactive effect to the stock split in these financial statements.


NOTE 4 - FEDERAL AND STATE INCOME TAX EXPENSE

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

NOTE 5 - ACCRUED LIABILITIES

        Accrued liabilities consist of the following:

<TABLE>
<CAPTION>
                                                                 MAY 2,        JANUARY 31,
                                                                  1999            1999
                                                              ------------    ------------
<S>                                                           <C>             <C>
Accrued compensation and benefits                             $  2,897,412    $  4,546,415
Sales tax payable                                                1,619,459         738,910
Reserve for store expansion/relocation and closing costs         1,238,089       1,322,077
Gift certificates and store merchandise credits                    631,715         969,378
Other accrued liabilities                                        1,333,807       1,114,003
                                                              ------------    ------------
                                                              $  7,720,482    $  8,690,783
                                                              ============    ============
</TABLE>

NOTE 6 - DEFERRED COMPENSATION AND OTHER ASSETS

        Deferred compensation and other assets consist of the following:


<TABLE>
<CAPTION>
                                 MAY 2,       JANUARY 31,
                                 1999            1999
                             ------------    ------------
<S>                          <C>             <C>
Deferred compensation        $  3,364,694    $  2,807,694
Covenant not-to-compete           166,666         179,167
Security deposits                 167,232         155,643
                             ------------    ------------
                             $  3,698,592    $  3,142,504
                             ============    ============
</TABLE>

NOTE 7 - NEW SUBSIDIARY; LIMITED LIABILITY COMPANY

        In March 1999, the Company formed Pacific Sunwear.com Corp, a
wholly-owned subsidiary, in order to sell merchandise over the internet. The
Company anticipates that it will begin selling merchandise over the internet in
the summer of 1999.

        In March 1999, the Company announced an agreement with Vans, Inc.
("Vans"), whereby a new limited liability company named Van Pac, LLC (the "LLC")
was created in order to produce and distribute Vans apparel. The apparel line
created by the LLC will initially be for sale in Pacific Sunwear and Vans stores
only. The Company will provide product development, design, sourcing, quality
control and inventory planning services to the LLC, while Vans will contribute
design services and license the VANS and TRIPLE CROWN trademarks and logos to
the LLC. Vans owns 51% of the LLC and the Company owns 49%. The LLC anticipates
launching the new line in the summer of 1999.


                                       7
<PAGE>   8
                MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                CONDITION AND RESULTS OF CONSOLIDATED OPERATIONS

RESULTS OF OPERATIONS

Thirteen weeks ended May 2, 1999 (first quarter) as compared to thirteen weeks
ended May 3, 1998 (first quarter)

        Net Sales

        Net sales increased to $81.4 million for the first thirteen weeks of
fiscal 1999 from $61.2 million for the first thirteen weeks of fiscal 1998, an
increase of $20.2 million, or 33.0%. Of this $20.2 million increase, $13.4
million was attributable to net sales generated by new stores opened in fiscal
1998, as well as Pacific Sunwear stores converted to "d.e.m.o." stores, and not
yet included in the comparable store base, $3.9 million was attributable to a
7.2% increase in comparable store net sales in the first thirteen weeks of
fiscal 1999, $2.1 million was attributable to net sales generated by 29 new
stores opened in fiscal 1999 not yet included in the comparable store base, and
$1.2 million was attributable to 17 Pacific Sunwear stores that have been
expanded or relocated to the larger format and not yet included in the
comparable store base. Partially offsetting this increase was a $.4 million
decrease in net sales attributable to the closing of four stores during fiscal
1998 and one store during fiscal 1999. The increase in comparable store net
sales was primarily attributable to increases in comparable store net sales of
junior apparel, footwear, accessories and, to a lesser extent, increases in
comparable store net sales of young men's merchandise. Retail prices of the
Company's merchandise remained relatively unchanged in the first thirteen weeks
of fiscal 1999 compared to the first thirteen weeks of fiscal 1998 and had no
significant impact on the net sales increase for the first thirteen weeks of
fiscal 1999.

        Gross Margin

        Gross margin, after buying, distribution and occupancy costs, increased
to $26.1 million for the first thirteen weeks of fiscal 1999 from $19.6 million
for the first thirteen weeks of fiscal 1998, an increase of $6.5 million, or
33.2%. As a percentage of net sales, gross margin was 32.1% for both the first
thirteen weeks of fiscal 1999 and the first thirteen weeks of fiscal 1998.
Occupancy costs for the first thirteen weeks of fiscal 1999 decreased .2% as a
percentage of net sales compared to the first thirteen weeks of fiscal 1998,
which was related to higher comparable store net sales. Offsetting this decrease
was a .2% increase in distribution costs as a percentage of net sales during the
first thirteen weeks of fiscal 1999 as compared to the first thirteen weeks of
fiscal 1998 primarily due to depreciation expense of the Company's new
distribution facility. The Company's new distribution facility was placed into
service and the Company began recording the related depreciation expense in the
second quarter of fiscal 1998.

        Selling, General and Administrative Expenses

        Selling, general and administrative expenses increased to $19.7 million
for the first thirteen weeks of fiscal 1999 from $15.1 million for the first
thirteen weeks of fiscal 1998, an increase of $4.6 million, or 30.5%. As a
percentage of net sales, these expenses decreased to 24.2% from 24.8%. Of this
 .6% net decrease as a percentage of net sales, .6% was due to a decrease in
general and administrative expenses as a percentage of net sales and .4% was due
to a decrease in store expansion/relocation and closing expenses as a percentage
of net sales. These decreases as a percentage of net sales were primarily a
result of leveraging these expenses over higher total net sales. Offsetting
these decreases was a .4% increase in store selling expenses as a percentage of
net sales, primarily due to an increase in advertising expense during the first
thirteen weeks of fiscal 1999 as compared to the first thirteen weeks of fiscal
1998. The Company initiated its first ever national print advertising campaign
in the first thirteen weeks of fiscal 1999.

        Income Tax Expense

        Income tax expense was $2.5 million for the first thirteen weeks of
fiscal 1999 compared to $1.9 million for the first thirteen weeks of fiscal
1998. The effective income tax rate was 38.5% for the first thirteen weeks of
fiscal 1999 as compared to 39.6% for the first thirteen weeks of fiscal 1998.
The lower effective income tax rate for the first thirteen weeks of fiscal 1999
was primarily attributable to a lower weighted effective state income tax rate
for the Company. The weighted effective state income tax rate of the Company
will vary depending on a variety of factors, such as varying income tax rates by
state and changes in the weighting formulas caused by the Company's growth by
state, as well as other factors.


                                       8
<PAGE>   9
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
fiscal 1998, the Company used funds for the relocation of and capital
improvements to its new corporate offices and distribution facility. In
addition, during the fourth quarter of fiscal 1998, the Company purchased and
retired 667,500 shares of its common stock at an average cost of $13.31 per
share for a total cost of $8.9 million. These purchases were made pursuant to a
resolution adopted by the Board of Directors in December 1998 which authorized
the Company to purchase up to 1.0 million shares of its common stock.

        Net cash provided by operating activities for the first thirteen weeks
of fiscal 1999 was $1.7 million compared to $3.1 million for the first thirteen
weeks of fiscal 1998. This $1.4 million decrease was primarily attributable to
an increase in merchandise inventories net of accounts payable of $4.6 million,
an increase in accounts receivable of $1.2 million, an increase in prepaid
expenses of $.9 million and net increases in other items netting to $1.0
million, offset by an increase in accrued income taxes and deferred income taxes
of $2.6 million, an increase in accrued liabilities of $1.5 million, an increase
in net income of $1.2 million and an increase in depreciation and amortization
of $1.0 million. Inventories at May 2, 1999 were $46.4 million compared to $42.5
million at January 31, 1999, an increase of $3.9 million. This increase was
primarily related to opening 29 new stores and expanding/relocating five stores
with in excess of 50% larger average square footage than their previous
locations.

        Net cash used in investing activities was $10.7 million for the first
thirteen weeks of fiscal 1999 compared to net cash provided by investing
activities of $.4 million for the first thirteen weeks fiscal 1998. Net cash
invested in property and equipment was $10.7 million for the first thirteen
weeks of fiscal 1999 compared to $9.5 million for the first thirteen weeks of
fiscal 1998. The increase in capital expenditures was primarily due to an
increase in the number of new stores opened. As of the first thirteen weeks of
fiscal 1998, the Company had short term investment maturities of $9.9 million.

        Net cash provided by financing activities for the thirteen weeks of
fiscal 1999 was $1.3 million compared to $.3 million for the first thirteen
weeks of fiscal 1998. In the first thirteen weeks of fiscal 1999, the Company
received proceeds of $1.3 million from the exercise of stock options compared to
$.3 million in the first thirteen weeks of fiscal 1998.

        The Company has a credit facility with a bank, which expires in August
2000. The credit facility provides for a $25.0 million line of credit, which can
be used for cash advances, commercial letters of credit and shipside bonds.
Interest on cash advances under the line of credit facility is payable monthly
at the bank's prime rate (7.75 % at May 2, 1999). At May 2, 1999, the Company
had $6.2 million in letters of credit outstanding. The loan agreement subjects
the Company to various restrictive covenants, including maintenance of certain
financial ratios and prohibits payment of cash dividends on common stock. At May
2, 1999, the Company was in compliance with all of the covenants.

        The Company plans to open approximately 83 new stores, of which 52 will
be Pacific Sunwear stores, 13 will be Pacific Sunwear Outlet stores and 18 will
be d.e.m.o. stores during the remainder of fiscal 1999. The Company also plans
to expand or relocate 10 existing smaller Pacific Sunwear stores during the
remainder of fiscal 1999. The Company estimates that capital expenditures during
the remainder of fiscal 1999 will be approximately $24 million.

        The Company reviews the operating performance of its stores on an
ongoing basis to determine which stores, if any, to close and records closing
costs as stores are closed or identified to be closed. The Company closed one
store in the first thirteen weeks of fiscal 1999. The Company anticipates
closing two additional stores in fiscal 1999.

        Management believes that the Company's working capital, bank line of
credit and cash flows from operating activities will be sufficient to meet the
Company's operating and capital expenditure requirements through the end of
fiscal 2000.


                                       9
<PAGE>   10
INFLATION

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

NEW ACCOUNTING PRONOUNCEMENTS

        Accounting for Derivatives and Hedging Activities -- In June 1998, the
FASB issued SFAS No. 133, "Accounting for Derivatives and Hedging Activities"
(SFAS 133). SFAS 133 must be implemented by the Company in fiscal 2000. SFAS 133
is not expected to have a significant impact on the Company's consolidated
financial statements.

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 fiscal 1998 and fiscal 1997,
excluding sales generated by new and relocated/expanded stores, the Christmas
and back-to-school periods together accounted for approximately 34% and 35%,
respectively, of the Company's annual net sales and a higher percentage of the
Company's operating income. In fiscal 1998, excluding net sales generated by new
and relocated/expanded stores, approximately 45% of the Company's annual net
sales occurred in the first half of the fiscal year and 55% 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.

YEAR 2000 READINESS

        The Company has completed a year 2000 review of its information
technology and non-information technology systems in preparation for the year
2000.

        The Company's material merchandise, financial and store computer
software systems are provided by third-party vendors and are used with minor
modifications by the Company. The software vendors have provided updated
software versions as part of the normal periodic software upgrade process that
address the year 2000 issue. This upgrade process has been substantially
completed as of the end of fiscal 1998 and did not cost the Company additional
amounts beyond normal recurring annual software maintenance fees paid by the
Company. While the Company will incur internal staff costs as well as certain
outside consulting and other expenditures related to its year 2000 readiness
efforts, the total incremental expenses are not expected to have a material
impact on the Company's financial condition or results of operations. As of May
2, 1999, the Company had incurred less than $150,000 in expenses relating to its
year 2000 readiness efforts. The source of funds for these expenses has been the
Company's working capital, and the Company anticipates that it will fund its
additional year 2000 expenses from its working capital.

        The Company's most significant software system includes purchase order
management, open order reporting, open-to-buy, receiving, distribution, basic
stock replenishment, inter-store transfers, inventory and price management,
general ledger and accounts payable functions. This system has been upgraded and
has been certified by the software vendor as year 2000 compliant. In addition,
the Company uses a recently installed materials handling system at its new
distribution center and the vendor of this system has advised the Company that
the system is year 2000 compliant.

        With regard to the Company's vendors, the Company has contacted its
significant merchandise vendors regarding their state of year 2000 readiness and
these vendors have advised the Company that they expect to be ready for the year
2000. None of these vendors accounted for more than 9% of the Company's net
sales in fiscal 1998. The Company also uses numerous third-party vendors to
provide other goods and services, as well as office, distribution center and
other supplies to the Company and its stores. The Company has contacted its
significant goods and services vendors regarding their state of year 2000
readiness and these vendors have advised the Company that they expect to be
ready for the year 2000. There is no assurance that the systems of the vendors
from whom the Company receives merchandise, goods and services will be year 2000
ready or that any failure on their part to be year 2000 ready would not have an
adverse impact on the Company if a number of such vendors fail to be year 2000
ready on a timely basis.


                                       10
<PAGE>   11
        The year 2000 issue presents a number of risks and uncertainties that
could impact the Company, from the failure of one or several of the Company's
significant vendors to timely fill the Company's merchandise orders to public
utility failures affecting the Company's retail stores. The Company is currently
analyzing these risks and uncertainties and has begun to develop contingency
plans to address material risks related to the year 2000 issues. These
contingency plans include the following:

        January 1, 2000 falls on a Saturday, when the Company's distribution
center and corporate offices are normally closed. The contingency plans include
operating the distribution center and corporate office systems on January 1 in
order to quickly address any year 2000 issues that may arise.

        The Company's shipment of merchandise to its stores is traditionally at
a low point during the time frame surrounding the immediate beginning of the new
year due to the fact that the stores are primarily engaged in the promotional
selldown of inventories after the holiday season. The Company plans to monitor
merchandise shipments from vendors during the weeks immediately following
January 1, 2000, and survey its vendors to determine if they are encountering
year 2000 issues that may prevent them from delivering future shipments of
merchandise on a timely basis. Contingency plans include processing substitute
orders with vendors that do not have year 2000 issues.

        The Company's stores will be open for business on January 1, 2000.
Contingency plans for the Company's stores include: (i) all stores will report
to the corporate office during the morning of January 1, 2000 whether they are
open and operating normally, or if they have encountered problems, (ii) a
procedure to rank year 2000 issues reported by stores in order of importance,
using the ability of the store to conduct business and process sales as the
primary criteria, (iii) the Company's staff of information systems personnel
will be on hand and available to work on any year 2000 issues on January 1, 2000
and (iv) the use of existing manual sales processing procedures in any affected
stores until such time as any year 2000 issues are fixed.

        While the Company continues to believe the year 2000 issues described
above will not materially affect its financial position or results of
operations, it remains uncertain as to what extent, if any, the Company may be
impacted.

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 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:

        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.

        RISKS OF NEW SPECIALTY STORE CONCEPT NAMED "D.E.M.O.". The Company's
ability to expand into new concepts has not been fully tested. The Company
opened the first d.e.m.o. store in April of fiscal 1998, and at the end of the
first thirteen weeks of fiscal 1999 operated 22 d.e.m.o. stores. Accordingly,
the operation of its d.e.m.o. stores is subject to numerous risks, including
unanticipated operating problems, lack of experience, lack of customer
acceptance, new vendor relationships and competition from existing and new
retailers. 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 also involves other
risks that could have a material adverse


                                       11
<PAGE>   12
effect on the Company, including (i) the diversion of management's attention
from the Company's core business, (ii) difficulties with the 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 intends to begin selling merchandise over
the internet in the summer of 1999. The internet operations involve, among other
things, internet web site design activities, investment in new systems,
distribution center enhancements, training of personnel and hiring of additional
personnel to handle new functions. The Company's internet operations will be
subject to numerous risks, including unanticipated operating problems, reliance
on third party computer hardware and software providers, higher than expected
volumes of traffic on the web site that could lead to system failures and the
need to invest in additional computer systems to support the traffic, lack of
experience in managing the new internet business, lack of customer acceptance
and lack of experience in the fulfillment and shipping of individual orders to
customers. 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 diversion of management's
attention from the Company's core business, (ii) the failure to reach
profitability within the foreseeable future, (iii) difficulties with hiring,
retention and training of key personnel to conduct the Company's internet
operations, (iv) diversion of sales from Pacific Sunwear stores, (v) rapid
technological change, (vi) liability for online content and (vii) 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 involves 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,
(vii) general economic conditions and economic conditions specific to the
internet, online commerce and the apparel industry and (viii) competition from
other internet web sites that may have significantly more capital resources and
experience in internet sales than the Company.

        EXPANSION AND MANAGEMENT OF GROWTH. Pacific Sunwear'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 1999, the Company plans to open
approximately 83 new stores, of which 52 will be Pacific Sunwear stores, 13 will
be Pacific Sunwear Outlet stores and 18 will be d.e.m.o. stores. The Company
also plans to expand or relocate 10 existing smaller Pacific Sunwear stores
during the remainder of fiscal 1999. 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 merchandise supply 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 continue to 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.

        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. Misjudgements
or unanticipated fashion misjudgements could have a material adverse effect on
the Company's image with its customers.

        PRIVATE BRAND MERCHANDISE. Sales from private brand merchandise
accounted for approximately 36% and 38% of net sales in fiscal 1998 and fiscal
1997, respectively. The Company intends to increase the percentage of net sales
in private brands in the future, although there can be no assurance that the
Company will be able to achieve increases in private brand sales as a percentage
of net sales. Because the Company's private brand merchandise


                                       12
<PAGE>   13
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 brand merchandise, particularly if the
percentage of net sales derived from private brand merchandise increases, may
have a material adverse affect 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.

        DEPENDANCE ON SINGLE DISTRIBUTION FACILITY. The Company's distribution
functions for all of its stores are handled from a single facility in Anaheim,
California. In addition, the Company intends initially to process shipments
related to sales of merchandise over the internet from the same facility. Any
significant interruption in the operation of the distribution facility due to
natural disasters, accidents, system failures arising from the year 2000 issue
or otherwise, would have a material adverse effect on the Company's business,
financial condition and results of operations.

        YEAR 2000 READINESS AND CONTINGENCY PLAN. There can be no assurance that
a failure in the Company's information and non-information technology systems
due to the year 2000 will not occur. Any significant failure due to the year
2000 could have a material adverse effect on the Company's business, financial
condition and results of operations. Examples of failures due to the year 2000
include, among others: (i) failures of one or several of the Company's
significant vendors to timely fill the Company's merchandise orders, (ii) public
utility failures that prevent some of the Company's stores from opening for
normal business hours, the Company's distribution center from handling
distribution functions, and/or the Company's corporate office from conducting
normal business, (iii) failures in the banking system, including the processing
of charge card, check and debit card transactions and (iv) other unforeseen
failures in the national infrastructure that the Company depends upon to conduct
its business.

        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, 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. For example, in December 1998 the Company's stock
price decreased dramatically after a decrease in the Company's comparable store
net sales for the month of November 1998 was reported. 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 small public companies for reason frequently unrelated to the operating
performance of the specific companies.

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

        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

        The Company is exposed to market risk related to changes in interest
rates. 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 January 31, 1999. The Company monitors the risks
associated with interest rates and financial instrument positions.


                                       13
<PAGE>   14
                            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 - Not Applicable

Item 5 - Other Information - Not Applicable

Item 6 - Exhibits and Reports on Form 8-K

        (a)     Exhibits:

                (27)    Financial Data Schedule

        (b)     Reports on Form 8-K:

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


                                       14
<PAGE>   15
                                   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: May 21, 1999                    /s/   GREG H. WEAVER
                                     -------------------------------------------
                                     Greg H. Weaver
                                     Chairman of the Board
                                     and Chief Executive Officer


Date: May 21, 1999                    /s/   CARL W. WOMACK
                                     -------------------------------------------
                                     Carl W. Womack
                                     Senior Vice President, Chief
                                     Financial Officer and Secretary


                                       15
<PAGE>   16
                                 EXHIBIT INDEX


EXHIBIT
NUMBER              DESCRIPTION
-------             -----------

  (27)      Financial Data Schedule