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 [X]    No [  ]

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):

Wisconsin Energy Corporation is a diversified holding company which conducts its operations primarily in three operating segments: a utility energy segment, a non-utility energy segment and a manufacturing segment. Unless qualified by their context when used in this document, the terms Wisconsin Energy, the Company, Our, Us or We refer to the holding company and all of its subsidiaries. Our primary subsidiaries are Wisconsin Electric Power Company (Wisconsin Electric), Wisconsin Gas Company (Wisconsin Gas), W.E. Power, LLC (We Power) and WICOR Industries, LLC (WICOR Industries).

Utility Energy Segment:   Our utility energy segment consists of: Wisconsin Electric, which serves electric customers in Wisconsin and the Upper Peninsula of Michigan, gas customers in Wisconsin and steam customers in metro Milwaukee, Wisconsin; Wisconsin Gas, which serves gas customers in Wisconsin and water customers in suburban Milwaukee, Wisconsin; and Edison Sault Electric Company (Edison Sault), which serves electric customers in the Upper Peninsula of Michigan. In April 2002, Wisconsin Electric and Wisconsin Gas began doing business under the trade name of "We Energies".

Non-Utility Energy Segment:   Our non-utility energy segment consists of We Power and Wisvest Corporation (Wisvest). We Power was formed in 2001 to design, construct, own, finance and lease the new generating capacity included in our Power the Future strategy. Wisvest owns and has investments in electric generating facilities and other energy-related entities and assets. We have reduced the operations of Wisvest.

Manufacturing Segment:   Our manufacturing segment consists of WICOR Industries, an intermediary holding company, and its three primary subsidiaries: Sta-Rite Industries, LLC (Sta-Rite), SHURflo, LLC (SHURflo) and Hypro, LLC (Hypro), which are manufacturers of pumps, water treatment products and fluid handling equipment with manufacturing, sales and distribution facilities in the United States and several other countries. In February 2004, we announced that we reached an agreement to sell this segment to Pentair, Inc. for $850 million and the assumption of approximately $25 million of debt. Subject to customary regulatory approvals, we expect the sale to close during the third quarter of 2004. Accordingly, this segment is reflected as discontinued operations in the accompanying financial statements.

Other:   Other non-utility operating subsidiaries of Wisconsin Energy include Minergy Corp. (Minergy), which has $54 million of assets and develops and markets recycling technologies, and Wispark LLC (Wispark), which has $151 million of assets and develops and invests in real estate.

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 ENERGY CORPORATION
NOTES TO CONSOLIDATED CONDENSED FINANCIAL STATEMENTS
(Unaudited)

Our accompanying unaudited consolidated 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 have modified certain income statement, balance sheet and cash flow presentations. Prior year financial statement amounts have been reclassified to conform to their current year presentation. These reclassifications had no effect on earnings per share.

The most significant reclassifications relate to the reporting of discontinued operations pursuant to Statement of Financial Accounting Standards (SFAS) 144, Accounting for the Impairment or Disposal of Long-Lived Assets. Previously, these were included as components of continuing operations. For further information see Note 3 -- Discontinued Operations and Assets Held for Sale.

Variable Interest Entities:   In January 2003, the Financial Accounting Standards Board (FASB) issued Interpretation 46, Consolidation of Variable Interest Entities (FIN 46). This standard requires an enterprise that is the primary beneficiary of a variable interest entity to consolidate that entity. We applied the Interpretation to any existing interests in variable interest entities beginning in the third quarter of 2003. In October 2003, the FASB deferred the adoption of FIN 46 for all entities commonly referred to as special-purpose entities to the first reporting period ending after December 15, 2003. In December 2003, the FASB issued FIN 46R, which revised FIN 46 and deferred the effective date for interests held in variable interest entities other than special purpose entities to financial statements for periods ending after March 15, 2004.

Upon adoption of FIN 46R in the first quarter of 2004, we evaluated several tolling and purchased power agreements with third parties and concluded that for three of these agreements, after making an exhaustive effort, we are unable to obtain the information necessary to determine whether we or the entity that owns the facility is the variable interest entity's primary beneficiary. Pursuant to the terms of two of the agreements, we deliver fuel to the entity's facilities and receive electric power. We pay the entity a "toll" to convert our fuel into the electric energy. The output of the facility is available for us to dispatch during the term of the respective agreement. In the other agreement we have rights to the firm capacity. We have approximately $788.9 million of required payments over the remaining term of the agreements, which expire in 5 to 25 years. We believe the required payments will continue to be recoverable in rates. We account for one of these agreements as a capita l lease.

On February 4, 2004, we announced that we had reached an agreement to sell our manufacturing business to Pentair, Inc. for $850 million in cash. In addition, Pentair will assume approximately $25 million of third party debt. This sale is subject to regulatory approvals and is expected to close in the third quarter of 2004. When the sale is completed, we expect to realize net cash proceeds of approximately $740 million after the payment of taxes and transaction costs.

In March 2004, WICOR, Inc. 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, is expected to result in Wisconsin Gas becoming a direct wholly-owned subsidiary of Wisconsin Energy.

In the accompanying balance sheets, the assets and liabilities associated with our manufacturing segment have been reclassified as held for sale in accordance with SFAS 144, Accounting for the Impairment or Disposal of Long-Lived Assets. SFAS 144 requires that a long-lived asset classified as held for sale be measured at the lower of its carrying amount or fair value, less costs to sell, and cease being depreciated. Included in discontinued operations is interest expense associated with third-party debt that will be assumed by the buyer upon completion of the sale. A summary of the components of Income from Discontinued Operations, Net of Tax in our Consolidated Condensed Income Statements follows: