<PAGE>   1
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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549
                   -------------------------------------------
                                    FORM 10-Q

(Mark one)

[X]    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
       EXCHANGE ACT OF 1934 FOR THE QUARTERLY PERIOD ENDED April 1, 2000

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

                         Commission file number 1-13474
                              FLORSHEIM GROUP INC.
             (Exact name of registrant as specified in its charter)

             Delaware                                            36-3520923
             --------                                            ----------
(State or other jurisdiction of                               (I.R.S. Employer
 incorporation or organization)                              Identification No.)

200 North LaSalle Street, Chicago, Illinois                       60601-1014
-------------------------------------------                       ----------
(Address of principal executive offices)                          (Zip Code)


        Registrant's telephone number, including area code (312) 458-2500
                                                            -------------

                                 Not Applicable
              ----------------------------------------------------
              (Former name, former address and former fiscal year,
                          if changed since last report)

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
requirement for the past 90 days. Yes [x] No [ ]

                      APPLICABLE ONLY TO CORPORATE ISSUERS:

Indicate the number of shares outstanding of each of the issuer's classes of
common stock, as of the latest practicable date.

                       8,483,651 Shares as of May 1, 2000


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<PAGE>   2



                          PART I FINANCIAL INFORMATION


ITEM 1.    FINANCIAL STATEMENTS


           Condensed Consolidated Balance Sheet:

                January 1, 2000 and April 1, 2000


           Condensed Consolidated Statement of Operations and Comprehensive
           Earnings:

                Three Months Ended April 3, 1999 and April 1, 2000


           Condensed Consolidated Statement of Cash Flows:

                Three Months Ended April 3, 1999 and April 1, 2000

           Notes to Condensed Consolidated Financial Statements



ITEM 2.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
           RESULTS OF OPERATIONS



ITEM 3.    QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK




                                       2

<PAGE>   3
                              FLORSHEIM GROUP INC.
                      CONDENSED CONSOLIDATED BALANCE SHEET
                                   (Unaudited)
                                 (In thousands)


<TABLE>
<CAPTION>
                                                    January 1,     April 1,
                                                      2000           2000
                                                    ---------    -----------
<S>                                                 <C>          <C>
                        ASSETS

Current assets:
     Cash and cash equivalents ..................   $   5,675    $   5,444
     Accounts receivable, net ...................      30,163       36,126
     Inventories ................................      70,964       66,893
     Other current assets .......................      11,082       11,319
                                                    ---------    ---------
       Total current assets .....................     117,884      119,782

Property, plant and equipment, net ..............      32,525       30,303
Deferred tax assets, net ........................      16,623       18,015
Other assets ....................................      30,320       30,826
                                                    ---------    ---------

     Total assets ...............................   $ 197,352    $ 198,926
                                                    =========    =========

         LIABILITIES AND SHAREHOLDERS' EQUITY

Current liabilities:
     Current portion of long-term debt ..........   $  23,767    $  16,500
     Accounts payable and accrued expenses ......      24,842       23,895
                                                    ---------    ---------
       Total current liabilities ................      48,609       40,395

Bank credit facility ............................      65,000       74,753
Other long-term debt ............................      18,412       21,265
Other long-term liabilities .....................      20,683       20,654
                                                    ---------    ---------
       Total liabilities ........................     152,704      157,067

Shareholders' equity:
     Common stock ...............................       8,484        8,484
     Paid in capital ............................      50,644       50,644
     Accumulated comprehensive loss-
       Translation adjustment ...................      (2,760)      (3,072)
     Accumulated deficit ........................     (11,720)     (14,197)
                                                    ---------    ---------
         Total shareholders' equity .............      44,648       41,859
                                                    ---------    ---------

       Total liabilities and shareholders' equity   $ 197,352    $ 198,926
                                                    =========    =========
</TABLE>



See accompanying notes to condensed consolidated financial statements.



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<PAGE>   4


                              FLORSHEIM GROUP INC.
    CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS AND COMPREHENSIVE EARNINGS
                                   (Unaudited)
                      (In thousands, except per share data)


                                               Three months      Three months
                                                  ended             ended
                                               April 3, 1999     April 1, 2000
                                               -------------     -------------

Net sales                                      $ 63,525             $ 56,221
Cost of sales                                    33,402               32,210
                                               --------             --------

Gross profit                                     30,123               24,011
Selling, general and administrative expenses     26,200               24,470
Non-recurring expenses                             --                   (923)
                                               --------             --------

Earnings (loss) from operations                   3,923               (1,382)
Interest expense, net                             2,397                3,024
Other income, net                                  --                    571
                                               --------             --------

Earnings (loss) before income taxes               1,526               (3,835)
Income tax expense (benefit)                        547               (1,358)
                                               --------             --------

Net earnings (loss)                                 979               (2,477)

Other comprehensive loss -
     Foreign currency translation adjustment       (138)                (312)
                                               --------             --------

Comprehensive earnings (loss)                  $    841             $ (2,789)
                                               ========             ========

Earnings (loss) per share:
     Basic                                     $   0.12             $  (0.29)
                                               ========             ========

     Diluted                                   $   0.11             $  (0.29)
                                               ========             ========


See accompanying notes to condensed consolidated financial statements.


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<PAGE>   5
                              FLORSHEIM GROUP INC.
                 CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS
                                 (In thousands)
                                   (Unaudited)


<TABLE>
<CAPTION>
                                                       Three months   Three months
                                                          ended          ended
                                                         April 3,       April 1,
                                                           1999            2000
                                                       -----------    ------------
<S>                                                    <C>               <C>
Cash flows from operating activities:
   Net earnings (loss)                                 $   979           $(2,477)
   Adjustments to reconcile net earnings (loss) to
     net cash used in operating activities:
       Gain on disposal of assets                          (10)             (619)
       Depreciation and amortization                     1,518             1,819
       Deferred taxes                                      491            (1,370)
       Noncash interest expense                            108               274
       Increase in receivables                          (2,596)           (5,253)
       Decrease (increase) in inventories                 (725)            4,071
       Increase in prepaid expenses and other assets    (1,598)           (1,439)
       Decrease in accounts payable and
         other accrued expenses                         (2,857)             (947)
       Decrease in other long-term liabilities             (28)              (29)
                                                       -------           -------

Net cash used in operating activities                   (4,662)           (5,970)
                                                       -------           -------

Cash flows from investing activities:
   Proceeds from the disposal of assets                     10               691
   Additions to property, plant and equipment           (1,594)             (291)
                                                       -------           -------

Net cash provided by (used in) investing activities     (1,584)              400
                                                       -------           -------

Cash flows from financing activities:
   Net borrowing under revolving credit facility         6,000             2,183
   Increase in other long-term debt                       --               3,156
                                                       -------           -------

Net cash provided by financing activities                6,000             5,339
                                                       -------           -------

Net decrease in cash and cash equivalents                 (246)             (231)
Cash and cash equivalent at beginning of period          6,931             5,675
                                                       -------           -------

Cash and cash equivalents at end of period             $ 6,685           $ 5,444
                                                       =======           =======

Supplemental disclosure:
   Cash payments for income taxes, net                 $ 1,221           $   381
   Cash payments for interest                          $ 2,756           $ 2,807

</TABLE>

See accompanying notes to condensed consolidated financial statements.



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<PAGE>   6
                              FLORSHEIM GROUP INC.
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                                  April 1, 2000
                                   (Unaudited)
                             (Dollars in thousands)


(1)      BASIS OF PRESENTATION

         The accompanying unaudited condensed consolidated financial statements
         of Florsheim Group Inc. ("Florsheim" or the "Company) have been
         prepared in accordance with generally accepted accounting principles
         for interim financial information and with the instructions to Form
         10-Q and Article 10 of Regulation S-X. Accordingly, they do not include
         all of the information and notes required by generally accepted
         accounting principles for complete financial statements. In the opinion
         of management, all adjustments, consisting of normal recurring
         adjustments, except as otherwise disclosed, considered necessary for a
         fair presentation have been included. Operating results for the three
         month period ended April 1, 2000 are not necessarily indicative of the
         results that may be expected for the year ending December 30, 2000.

         The balance sheet at January 1, 2000 has been derived from the audited
         consolidated financial statements at that date, but does not include
         all of the information and notes required by generally accepted
         accounting principles for complete financial statements.

         For further information, refer to the consolidated financial statements
         and notes thereto included in the Company's annual report on Form 10-K
         for the fiscal year ended January 1, 2000.

(2)      INVENTORIES
         Inventories are summarized as follows:


                                      January 1,    April 1,
                                       2000           2000
                                      ---------     --------

                 Retail merchandise   $34,329       $36,155
                 Finished products     32,682        28,256
                 Raw materials          3,953         2,482
                                      -------       -------
                                      $70,964       $66,893
                                      =======       =======

(3)      LONG TERM DEBT

         In May 2000, the Company amended its bank credit facility, resulting in
         a waiver of the financial covenant related to the EBITDA to interest
         expense ratio for the quarter ended April 1, 2000. In addition, the
         amendment reset this covenant and established new financial covenants
         commencing with the quarter ending July 1, 2000. The new covenants



                                       6

<PAGE>   7
                             FLORSHEIM GROUP INC.
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                                  April 1, 2000
                                   (Unaudited)
                             (Dollars in thousands)


         include additional requirements related to levels of senior debt to
         EBITDA and total debt to EBITDA.

(4)      NON-RECURRING EXPENSES

         The Company recorded a $923 pretax charge in the quarter ended April 1,
         2000. The charge consisted of $627 for costs associated with the
         downsizing of the Company's corporate headquarters space, including the
         write-off of certain leasehold improvements, lease termination costs
         and move expenses. Of these costs, $310 were non-cash. The charge also
         included severance costs for approximately 20 people located primarily
         at the Company's corporate headquarters.

         The following table summarizes the costs reflected in the Condensed
         Consolidated Financial States as of and for the quarter ended April 1,
         2000:


<TABLE>
<CAPTION>
                                                   Accrued                           Amounts        Accrued
                                                  Balance at        Additional       Charged       Balance at
                                                January 1, 2000     Provision       to Accrued    April 1, 2000
                                                ---------------     ----------      ----------    -------------
<S>                                             <C>                 <C>             <C>           <C>
         Resignation/Strategic Study
           Legal and professional fees          $     254            $     --       $       0     $       254
           Employee related expenses                  365                  --            (160)            205
                                                ---------            --------       ---------     -----------
                                                      619                  --            (160)            459
                                                ---------            --------       ---------     -----------

         Cape Girardeau Closing
           Inventory write-offs                       610                  --             (85)            525
           Plant and equipment costs                  437                  --             (77)            360
           Employee related expenses                  566                  --            (441)            125
                                                ---------            --------       ---------     -----------
                                                    1,613                  --            (603)          1,010
                                                ---------            --------       ---------     -----------

         Facility Downsizing/Golf Sale
           Inventory write-offs                       300                  --              --             300
           Receivables allowance                      365                  --              --             365
           Facilities charges                         276                 627            (356)            547
           Employee related expenses                  195                 296            (161)            330
                                                ---------            --------       ---------      ----------
                                                    1,136                 923            (517)          1,542
                                                ---------            --------       ---------      ----------

                  Total                         $   3,368            $    923       $  (1,280)     $    3,011
                                                =========            ========       =========      ==========
</TABLE>



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<PAGE>   8
                             FLORSHEIM GROUP INC.
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                                  April 1, 2000
                                   (Unaudited)
                             (Dollars in thousands)


(5)      OTHER INCOME

         During the first quarter of 2000 the Company recorded a $587 pretax
         gain related to the sale of the Cape Girardeau, Missouri facility. The
         gain is included in other income.

(6)      EARNINGS PER SHARE

         The Company presents basic and diluted earnings per share. Basic
         earnings per share excludes dilution and is computed by dividing income
         available to common stockholders by the weighted average number of
         common shares outstanding for the period. Diluted earnings per share
         reflect the potential dilution that could occur if securities or other
         contracts to issue common stock were exercised. Basic and diluted
         earnings per share do not include securities in instances where they
         would be antidilutive.

         The following table provides a reconciliation of the weighted average
         shares outstanding used in calculating basic and diluted earnings per
         share (in 000's):


                                                     Fiscal Quarter Ended
                                                   ------------------------

                                                    April 3,       April 1,
                                                     1999            2000
                                                    -------        --------
         Weighted average shares
           outstanding - basic                       8,454           8,484
         Assumed exercise of stock options              72            --
                                                     -----           -----
         Weighted average shares
           outstanding - diluted                     8,526           8,484
                                                     =====           =====



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                             FLORSHEIM GROUP INC.
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                                  April 1, 2000
                                   (Unaudited)
                             (Dollars in thousands)


(7)      BUSINESS SEGMENT INFORMATION

         Operating segment information is as follows:


                                          Fiscal Quarter Ended
                                         ----------------------
                                          April 3,    April 1,
                                            1999        2000
                                         ---------    ---------

Net Sales
  U.S. Wholesale                         $  26,607    $  24,674
  U.S. Retail                               25,012       21,405
  International                             11,906       10,142
                                         ---------    ---------
                                         $  63,525    $  56,221
                                         =========    =========

Earnings (Loss) from Operations
  U.S. Wholesale                         $   3,328    $   1,273
  U.S. Retail                                 (655)      (3,412)
  International                              1,250          757
                                         ---------    ---------
                                         $   3,923    $  (1,382)
                                         =========    =========


                                         January 1,    April 1,
                                            2000         2000
                                         ---------    ---------

Total Assets
  U.S. Wholesale                         $ 105,956    $ 104,564
  U.S. Retail                               69,112       71,944
  International                             22,284       22,418
                                         ---------    ---------
                                         $ 197,352    $ 198,926
                                         =========    =========


U.S. Wholesale includes certain corporate expenses and assets which are not
charged to other reportable segments. The April 1, 2000 period included $923 of
non-recurring expenses, which are included in U.S. Wholesale, related to
downsizing of the Company's corporate headquarters space and severance.



                                    9
<PAGE>   10



ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS

RESULTS OF OPERATIONS

Three Months ended April 1, 2000 Compared to the Three Months ended April 3,
1999

Net sales for the three months ended April 1, 2000 were $56.2 million, down $7.3
million, or 11.5%, as compared to the three months ended April 3, 1999. Net
sales were negatively impacted by inventory problems related to the
implementation of the Company's new wholesale computer software system in 1999.
The system problems resulted in reduced shipments to wholesale customers as well
as to the Company's U.S. Retail business as the Company was unable satisfy
customer orders. U.S. Wholesale sales were $24.7 million in 2000 compared to
$26.6 million in 1999 as result of the inventory problems. U.S. Retail net sales
decreased $3.6 million, or 14.4% to $21.4 million, primarily as a result of
planned store closings in 1999 and inventory shortages during the first two
months of the quarter. The inventory position improved in March, resulting in
improved sales, but the improvement was not sufficient to offset the shortfall
in the first two months of the quarter. U.S. Specialty Stores same store sales
decreased 1.4% over the comparable 1999 period. International sales decreased
$1.8 million to $10.1 million, due largely to the lack of inventory.

Gross profit margin for the first quarter 2000 was $24.0 million or 42.7% of net
sales, as compared to 47.4% of net sales for the first quarter 1999. Gross
profit margin was negatively impacted by the lower sales volume in each of the
businesses and the sale of close out products.

Selling, general and administrative expenses for the first quarter 2000 were
$24.5 million, a decrease of $1.7 million from the first quarter 1999. Selling,
general and administrative expenses for the first quarter 2000 were 43.5% of net
sales, an increase from 41.2% of net sales for the first quarter of 1999. The
decrease in expense was the result of cost reduction programs initiated in the
fourth quarter of 1999, and to a lesser extent, the reduced sales volume.

Non-recurring expenses of $0.9 million were recorded in the first quarter of
2000. The charge included $0.6 million related to the downsizing of the
Company's corporate headquarters space. Approximately $0.3 million of these
costs were non-cash. The remaining portion of the non-recurring expense of $0.3
million related to severance and associated benefit costs.

Interest expense for the first quarter 2000 was $3.0 million as compared to the
first quarter 1999 amount of $2.4 million. This increase is due to increased
borrowings during the first quarter 2000 as compared to the first quarter 1999
and an increase in the weighted average interest rate under the Company's new
credit facility.

Other income for the first quarter includes a $587 gain on the sale of the
Company's Cape Girardeau, Missouri, manufacturing facility which was closed in
December 1999. The sale of the facility was completed in January 2000.




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<PAGE>   11
ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
        RESULTS OF OPERATIONS


RESULTS OF OPERATIONS (CONT'D)

Income tax benefit for the first quarter of 2000 was $1.4 million, compared to
income tax expense of $0.5 million in the 1999 period. The effective tax rate
for 2000 was 35.4% compared to 35.8% in 1999.

LIQUIDITY AND CAPITAL RESOURCES

Working Capital

Working capital at April 1, 2000 was $79.4 million, as compared to $69.3 million
at January 1, 2000. The increase in working capital reflects an increase in
accounts receivable and the reclassification of certain debt to long term,
partially offset by reduced inventory levels.

In May 2000, the Company amended its bank credit facility, resulting in a waiver
of the financial covenant related to the EBITDA to interest expense ratio for
the quarter ended April 1, 2000. In addition, the amendment reset this covenant
and established new financial covenants commencing with the quarter ending July
1, 2000. The new covenants include additional requirements related to levels of
senior debt to EBITDA and total debt to EBITDA.


FORWARD LOOKING STATEMENTS

When used in this discussion, the words "believes" and "expects" and similar
expressions are intended to identify forward-looking statements. Such statements
are subject to certain risks and uncertainties, over which the Company has no
control, which could cause actual results to differ materially from those
projected. Readers are cautioned not to place reliance on these forward-looking
statements, which speak only as of the date hereof. The Company undertakes no
obligations to republish revised forward-looking statements to reflect events or
circumstances after the date thereof or to reflect the occurrence of
unanticipated events. Readers are also urged to carefully review and consider
the various disclosures made by the Company in this report, as well as the
Company's periodic reports with the Securities Exchange Commission.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISKS

There have been no material changes in the Company's market risk during the
three month period ended April 1, 2000. For additional information, refer to
Item 7A in the Company's Annual Report on form 10-K for the year ended January
1, 2000.



                                       11


<PAGE>   12

                            PART II OTHER INFORMATION


Item 4. Exhibits and Reports on Form 8-K

(a)      The following exhibits are filed as part of this report:

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

                  4.1      Second Amendment, dated as of May 15, 2000 to the
                           Credit Agreement dated August 23, 1999 among the
                           Company and BT Commercial Corporation, as Agent, and
                           Lenders party thereto.

                 27        Financial Data Schedule

(b)      Form 8-K was not required to be filed during the quarter ended April 1,
         2000.



                                       12


<PAGE>   13



                                    SIGNATURE

         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.


                                                     FLORSHEIM GROUP INC.
                                                        (Registrant)




                                                 By   /s/ Richard Anglin
                                                      Richard J. Anglin
                                                      Executive Vice-President,
                                                      Chief Financial Officer




         Date:  May 16, 2000




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<PAGE>   14






                                 EXHIBIT INDEX

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

                  4.1      Second Amendment, dated as of May 15, 2000 to the
                           Credit Agreement dated August 23, 1999 among the
                           Company and BT Commercial Corporation, as Agent, and
                           Lenders party thereto.

                 27        Financial Data Schedule