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

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 each Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes [X]    No [  ]

Indicate by check mark whether the Registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange Act).    Yes [  ]    No [X]

Indicate the number of shares outstanding of each of the Registrant's classes of common stock as of the latest practicable date (March 31, 2004):

All of the common stock of Wisconsin Gas Company is held by WICOR, Inc., a wholly owned subsidiary of Wisconsin Energy Corporation.

Wisconsin Gas Company (Wisconsin Gas, the Company, Our, Us or We), a natural gas distribution public utility, which serves approximately 572,000 gas customers in Wisconsin, is a Wisconsin corporation and is a wholly-owned, indirect subsidiary of Wisconsin Energy Corporation (Wisconsin Energy) and a direct wholly-owned subsidiary of WICOR, Inc (WICOR). Wisconsin Energy has integrated the gas operations and corporate support areas of Wisconsin Electric Power Company (Wisconsin Electric), Wisconsin Energy's wholly-owned electric, gas and steam utility, with Wisconsin Gas. In April 2002, Wisconsin Electric and Wisconsin Gas began doing business under the trade name "We Energies".

In March 2004, in connection with the previously announced pending sale of WICOR and its manufacturing subsidiary WICOR Industries, LLC to Pentair, Inc., WICOR applied to the Public Service Commission of Wisconsin (PSCW) for approval to transfer its current ownership interest in Wisconsin Gas to Wisconsin Energy, which, if approved, would result in us becoming a direct wholly-owned subsidiary of Wisconsin Energy.

We have prepared the unaudited interim financial statements presented in this Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission. We have condensed or omitted some information and note disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles pursuant to these rules and regulations. Our financial statements should be read in conjunction with the financial statements and notes thereto included in our 2003 Annual Report on Form 10-K.

WISCONSIN GAS COMPANY
NOTES TO CONDENSED FINANCIAL STATEMENTS
(Unaudited)

Our accompanying unaudited condensed financial statements should be read in conjunction with Item 8, Financial Statements and Supplementary Data, in our 2003 Annual Report on Form 10-K. In the opinion of management, we have included all adjustments, normal and recurring in nature, necessary to a fair statement of the results of operations, cash flows and financial position in the accompanying income statements, statements of cash flows and balance sheets. The results of operations for the three months ended March 31, 2004 are not necessarily indicative of the results which may be expected for the entire fiscal year 2004 because of seasonal and other factors.

We account for goodwill under Statement of Financial Accounting Standards (SFAS) 142, Goodwill and Other Intangible Assets. Under SFAS 142, goodwill is not subject to amortization. However, goodwill is subject to fair value-based rules for measuring impairment, and resulting write-downs, if any, are to be reflected in operating expense.

We assess the fair value of our goodwill by considering fair value based on public company trading multiples and merger and acquisition transaction multiples for similar companies. This evaluation utilizes the information available under the circumstances, including reasonable and supportable assumptions and projections. We perform our annual impairment test as of August 31.

Comprehensive Income:   Comprehensive Income includes all changes in equity during a period except those resulting from investments by and distributions to owners. We had the following total Comprehensive Income during the three months ended March 31, 2004 and 2003:

The components of our net periodic pension and other post-retirement benefit costs for the three months ended March 31, 2004 and 2003 were as follows:

We previously disclosed that we expect to contribute $0.6 million to our qualified pension plans in 2004. This contribution is expected to occur in September 2004. Any contribution in 2004 to other post-retirement benefit plans is expected to occur in December. This contribution is discretionary as these plans are not subject to any minimum regulatory funding requirements.

Employee Benefit Plans and Post-retirement Benefits:   In December 2003, the Medicare Prescription Drug, Improvement and Modernization Act of 2003 (Act) was signed into law. The Act introduced a prescription drug benefit program under Medicare as well as a federal subsidy to sponsors of retiree health care benefit plans. Certain accounting issues raised by the Act, such as how to account for the federal subsidy, are not explicitly addressed by SFAS 106, Employers' Accounting for Post-retirement Benefits Other Than Pensions.

The Financial Accounting Standards Board (FASB) issued FASB Staff Position (FSP) SFAS 106-1, Accounting and Disclosure Requirements Related to the Medicare Prescription Drug, Improvement and Modernization Act of 2003 (FSP 106-1) that allows sponsors to elect to defer recognition of the effects of the Act.

We are in the process of evaluating the impact of the Act on our U.S. post-retirement health plans. During this period, in accordance with FSP 106-1, we have elected to defer recognition of the effects of the Act. Accordingly, the financial statements do not reflect the effects of the Act. Upon the issuance of final guidance on this matter by the FASB, previously issued financial statements may require restatement and future results of operations may be impacted. That accounting guidance is expected to be issued by the FASB in the second quarter of 2004.

Postemployment benefits:   Postemployment benefits provided to former or inactive employees are recognized when an event occurs. The estimated liability for such benefits has not changed significantly from the $2.9 million accrual we recorded as of December 31, 2003.

Environmental Matters:   We periodically review our exposure for remediation costs as evidence becomes available indicating that our remediation liability has changed. Based on current information, management believes that future costs in excess of the amounts accrued and/or disclosed on all presently known and quantifiable environmental contingencies will not be material to our financial position or results of operations.

Cautionary Factors:   Certain statements contained herein are "Forward-Looking Statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-Looking Statements may be identified by reference to a future period or periods or by the use of forward looking terminology such as "may," "intends," "anticipates," "believes," "estimates," "expects," "forecasts," "objectives," "plans," "possible," "potential," "project" or similar terms or variations of these terms. Actual results may differ materially from those set forth in Forward-Looking Statements as a result of certain risks and uncertainties, including but not limited to, changes in political and economic conditions, equity and bond market fluctuations, varying weather conditions, governmental regulation and supervision, as well as other risks and uncertainties detailed from time to time in our filings with the Securities and Exchange Commission (SEC) including factors described throughout this document and below in "Factors Affecting Results, Liquidity and Capital Resources".

Net Income for the first quarter of 2004 was $23.3 million or 13.7% less than the first quarter of 2003, primarily reflecting warmer weather in 2004, increases in costs linked to changes in Wisconsin's public benefits legislation, benefit costs and higher interest expense. A more detailed analysis of financial results follows.

A comparison follows of our gas utility operating revenues, gross margin and gas deliveries during the first quarter of 2004 with similar information for the first quarter of 2003 including favorable (better (B)) or unfavorable (worse (W)) variances. Gross margin is a better performance indicator than revenues because changes in the cost of gas sold flow through to revenue under gas cost recovery mechanisms. Gas operating revenues decreased by $8.4 million or 2.7% due primarily to a weather-related decrease in the therm deliveries between the comparative periods offset by a $6.7 million or 2.9% decrease in purchased gas costs.

For the three months ended March 31, 2004, gas margins decreased $1.7 million or 2.0%, due primarily to warmer winter weather as compared to 2003. As measured by heating degree days, the first quarter of 2004 was 5.1% warmer than the first quarter of 2003 but 1.9% colder than normal.

The decrease in therm deliveries due to weather was offset in part by a rate increase effective in March 2004. We filed a limited rate adjustment request in July 2003 for gas rates for anticipated 2004 revenue deficiencies associated with costs for the Ixonia Lateral, which was placed into service in December 2003. In February 2004, the Public Service Commission of Wisconsin (PSCW) approved an increase in gas rates of $25.9 million. The increase in rates realized in the first quarter of 2004 was approximately $2.3 million compared with the same period in 2003.

The following table compares our gas utility gross margin and natural gas therm deliveries by customer class during the first quarter of 2004 with similar information for the first quarter of 2003.

Other Operation and Maintenance Expenses:   Other operation and maintenance expenses increased by $2.3 million or 7.7% during the first quarter of 2004 when compared with the first quarter of 2003. The increase was primarily attributable to approximately $0.6 million for increased benefit costs and $1.9 million of additional costs linked to changes in Wisconsin's public benefits legislation. Partial recovery of the additional costs associated with the Wisconsin public benefits legislation is included in the rate increase effective March 2004.

Interest Expense:   Interest expense increased by $1.8 million for the three months ended March 31, 2004 compared to the same period in 2003. This increase reflects the December 2003 issuance of $125 million of unsecured 5.20% Debentures due December 1, 2015, the proceeds of which were used to reduce short-term borrowings.

Income Taxes:   For the first quarter of 2004, our effective tax rate was 35.8%, which was slightly lower than the final rate for 2003 which was 35.9%.

The following summarizes our cash flows during the first three months of 2004 and 2003:

Cash provided by operating activities increased to $89.1 million during the first three months of 2004 compared with $53.2 million during the same period in 2003. This increase was due in large part to lower working capital requirements between the comparative periods resulting from warmer winter weather and greater draw downs of gas inventories in 2004.

During the first three months of 2004, we invested a total of $11.5 million, a decrease of $3.4 million over the prior year.

During the three months ended March 31, 2004, we reduced short-term borrowings by $77.3 million compared with a reduction of $38.9 million for the first three months of 2003. Our earnings and cash flows are seasonal.

Cash requirements during the remaining nine months of 2004 are expected to be met primarily through internally generated funds, short-term borrowings and existing lines of credit.

We have access to outside capital markets and have been able to generate funds internally and externally to meet our capital requirements. Our ability to attract the necessary financial capital at reasonable terms is critical to our overall strategic plan. We believe that we have adequate capacity to fund our operations for the foreseeable future through our borrowing arrangements and internally generated cash.

We have approximately $200 million of available unused lines of bank back-up credit facilities. On March 31, 2004, we had approximately $55.8 million of total short-term debt outstanding.

We review our bank back-up credit facility needs on an ongoing basis and expect to be able to maintain adequate credit facilities to support our operations. The following table summarizes such facilities at March 31, 2004:

The following table shows our capitalization structure at March 31, 2004 and at December 31, 2003:

Access to capital markets at a reasonable cost is determined in large part by credit quality. The following table summarizes the ratings of our debt securities by Standard & Poors Corporation (S&P), Moody's Investors Service (Moody's) and Fitch Ratings (Fitch) as of March 31, 2004.

The security rating outlooks assigned by S&P, Moody's and Fitch for us are all stable.

We believe these security ratings should provide a significant degree of flexibility in obtaining funds on competitive terms. However, these security ratings reflect the views of the rating agencies only. An explanation of the significance of these ratings may be obtained from each rating agency. Such ratings are not a recommendation to buy, sell or hold securities, but rather an indication of creditworthiness. Any rating can be revised upward or downward or withdrawn at any time by a rating agency if it decides that the circumstances warrant the change. Each rating should be evaluated independently of any other rating.

Capital requirements during the remainder of 2004 are expected to be principally for capital expenditures. Our 2004 annual capital expenditure budget is approximately $72 million.

Off-Balance Sheet Arrangements:   We are a party to various financial instruments with off-balance sheet risk as a part of our normal course of business, which may include, from time to time, financial guarantees and letters of credit, which support construction projects, commodity contracts and other payment obligations. Our estimated maximum exposure under these agreements is zero as of March 31, 2004.

Contractual Obligations/Commercial Commitments:   Our total contractual obligations and other commercial commitments as of March 31, 2004 decreased compared with December 31, 2003 as periodic

Credit Rating Risk:   We do not have any credit agreements that would require material changes in payment schedules or terminations as a result of a credit rating downgrade. We do have certain agreements in the form of commodity and energy services contracts and employee benefit plans that could require collateral or termination payments in the event of a credit ratings change to below investment grade. At March 31, 2004, we estimate that the potential payments under these agreements that could result from credit rating downgrades totaled approximately $0.7 million.

Limited Rate Adjustment Request:   On July 2, 2003, we filed an application with the PSCW for an increase in gas rates for anticipated 2004 revenue deficiencies associated with costs for construction of the Ixonia Lateral and increased costs linked to changes in Wisconsin's public Benefits legislation. The filing identified anticipated revenue deficiencies in 2004 in the amount of $26.2 million (3.9%). The PSCW approved an increase in gas rates of $25.9 million in an order effective March 2004.

New Pronouncements:   The FASB issued FASB Staff Position (FSP) 106-1, Accounting and Disclosure Requirements Related to the Medicare Prescription Drug, Improvement and Modernization Act of 2003 (FSP 106-1) that allows sponsors to elect to defer recognition of the effects of the Act. In accordance with FSP 106-1, we elected to defer recognition of the effects of the Act. Specific authoritative guidance on the accounting for the federal subsidy is pending and that guidance, when issued, could require us to change previously reported information. For further information, see "Note 4 -- Benefits" in the Notes to Condensed Financial Statements in Item 1 of Part I of this report.

This report and other documents or oral presentations contain or may contain forward-looking statements made by or on behalf of us. Such statements are based upon management's current expectations and are subject to risks and uncertainties that could cause our actual results to differ materially from those contemplated in the statements. Readers are cautioned not to place undue reliance on the forward-looking statements. When used in written documents or oral presentations, the terms "anticipate," "believe," "estimate," "expect," "forecast," "objective," "plan," "possible," "potential," "project" and similar expressions are intended to identify forward-looking statements. In addition to the assumptions and other factors referred to specifically in connection with such statements, factors that could cause our actual results to differ materially from those contemplated in any forward-looking statements include, among others, the following:

• Factors affecting utility operations such as: unusual weather conditions; catastrophic weather-related or terrorism-related damage; unplanned maintenance or repairs; unanticipated changes in gas supply or water supply costs or availability due to higher demand, shortages, transportation problems or other developments; nonperformance by natural gas suppliers under existing gas supply contracts; environmental incidents; gas pipeline system constraints; unanticipated organizational structure or key personnel changes; collective bargaining agreements with union employees or work stoppages; inflation rates; or demographic and economic factors affecting utility service territories or operating environment.

• Regulatory factors such as: unanticipated changes in rate-setting policies or procedures; unanticipated changes in regulatory accounting policies and practices; industry restructuring initiatives; distribution system operation and/or administration initiatives; recovery of costs of previous investments made under traditional regulation; recovery of costs associated with adoption of changed accounting standards; required changes in facilities or operations to reduce the risks or impacts of potential terrorist activities; required approvals for new construction; or changes in the regulations from the Wisconsin Department of Natural Resources related to the siting approval process for new pipeline construction.

• Unexpected difficulties or unanticipated effects of the qualified five-year electric and gas rate freeze ordered by the Public Service Commission of Wisconsin as a condition of its approval in 2000 of the merger of Wisconsin Energy Corporation and WICOR, Inc.

• The changing gas utility environment as market-based forces replace strict industry regulation and other competitors enter the gas markets resulting in increased wholesale and retail competition.

• Consolidation of the industry as a result of the combination and acquisition of utilities in the Midwest, nationally and globally.

• Changes in social attitudes regarding the utility and power industries.

• Customer business conditions including demand for their products or services and supply of labor and material used in creating their products and services.

• The cost and other effects of legal and administrative proceedings, settlements, investigations and claims, and changes in those matters.

• Factors affecting the availability or cost of capital such as: changes in interest rates and other general capital market conditions; our capitalization structure; market perceptions of the utility industry or us; or security ratings.

• Federal, state or local legislative factors such as changes in tax laws or rates; changes in trade, monetary and fiscal policies, laws and regulations; gas industry restructuring initiatives; changes in environmental laws and regulations; or changes in allocation of energy assistance, including state public benefits funds.

• Authoritative generally accepted accounting principle or policy changes from such standard setting bodies as the Financial Accounting Standards Board, the Securities and Exchange Commission and the Public Company Accounting Oversight Board.

• Unanticipated technological developments that result in competitive disadvantages and create the potential for impairment of existing assets.

• Other business or investment considerations that may be disclosed from time to time in our Securities and Exchange Commission filings or in other publicly disseminated written documents.

We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

*****

For certain other information which may impact our future financial condition or results of operations, see Item 1, Financial Statements -- "Notes to Condensed Financial Statements," in Part I of this report as well as Item 1, Legal Proceedings, in Part II of this report.

For information concerning market risk exposures at Wisconsin Gas Company, see Item 2, Management's Discussion and Analysis of Financial Condition and Results of Operations -- "Factors Affecting Results, Liquidity and Capital Resources -- Market Risks and Other Significant Risks" in Part I of this report. For information concerning other market risk exposures, see Item 7, Management's Discussion and Analysis of Financial Condition and Results of Operations -- "Factors Affecting Results, Liquidity and Capital Resources - Market Risks and Other Significant Risks," in Part II of Wisconsin Gas' 2003 Annual Report on Form 10-K.

Disclosure Controls and Procedures:   Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, have evaluated the effectiveness of our disclosure controls and procedures (as such term is defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (Exchange Act)) as of the end of the period covered by this report. Based on such evaluation, our Chief Executive Officer and Chief Financial Officer have concluded that, as of the end of such period, our disclosure controls and procedures are effective in recording, processing, summarizing and reporting, on a timely basis, information required to be disclosed by us in the reports that we file or submit under the Exchange Act.

Internal Control Over Financial Reporting:   There have not been any changes in our internal control over financial reporting (as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the fiscal quarter to which this report relates that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

The following should be read in conjunction with Item 3, Legal Proceedings, in Part I of our 2003 Annual Report on Form 10-K.

In addition to those legal proceedings discussed in our reports to the SEC, we are currently, and from time to time, subject to claims and suits arising in the ordinary course of business. Although the results of these legal proceedings cannot be predicted with certainty, management believes, after consultation with legal counsel, that the ultimate resolution of these proceedings will not have a material adverse effect on our financial statements.

See Item 2, Management's Discussion and Analysis of Financial Condition and Results of Operations - "Factors Affecting Results, Liquidity and Capital Resources" in Part I of this report for information concerning rate matters in the jurisdiction where we do business.

The following Exhibits are filed with or incorporated by reference in this Form 10-Q report:

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.