UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

February 14, 2011

Serena Software, Inc.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (650) 481-3400

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Serena Software, Inc. (“Serena”) is currently in the process of seeking an amendment to its Credit Agreement, dated as of March 10, 2006 (as heretofore amended, the “Credit Agreement”), by and among Spyglass Merger Corp., Serena Software, Inc., the joint lead arrangers and joint lead bookrunners, the administrative agent and collateral agent, the syndication agent, and the documentation agent, that, among other things, would amend the Credit Agreement to re-set covenant levels and extend the maturity dates of the revolving credit and term loans by an additional three years. Currently, Serena is required to maintain a maximum total leverage ratio of 5.00x. Under the terms of the proposed amendment, the maximum total leverage ratio would step up to 5.50x through the period ending on July 31, 2012 and would step down to 5.00x thereafter. The terms of the proposed amendment are preliminary and subject to review and approval by the requisite lenders and Serena and are therefore subject to further revision in connection with the amendment process.

Serena is providing the following unaudited guidance for its fiscal year ended January 31, 2011:

Earnings before interest, taxes, depreciation and amortization, or EBITDA, is a non-GAAP financial measure used to determine Serena’s compliance with certain covenants contained in the Credit Agreement. Adjusted EBITDA represents EBITDA further adjusted to exclude certain defined unusual items and other adjustments permitted in calculating covenant compliance under the Credit Agreement. Serena believes that the presentation of Adjusted EBITDA is appropriate to provide additional information to investors regarding its compliance with the financial covenants under the Credit Agreement.

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Adjusted EBITDA does not represent net income (loss) or cash flow from operations as those terms are defined by GAAP and does not necessarily indicate whether cash flows will be sufficient to fund cash needs. While Adjusted EBITDA and similar measures are frequently used as measures of operations and the ability to meet debt service requirements, these terms are not necessarily comparable to other similarly titled captions of other companies due to the potential inconsistencies in the method of calculation. Adjusted EBITDA does not reflect the impact of earnings or charges resulting from matters that Serena may consider not to be indicative of its ongoing operations. In particular, the definition of Adjusted EBITDA in the Credit Agreement allows it to add back certain defined non-cash, extraordinary, unusual or non-recurring charges that are deducted in calculating GAAP net income (loss). The Credit Agreement requires that Adjusted EBITDA be calculated for the most recent four fiscal quarters. As a result, Adjusted EBITDA can be disproportionately affected by a particularly strong or weak quarter and may not be comparable to Adjusted EBITDA for any subsequent four-quarter period or any complete fiscal year.

The following is a reconciliation of net income (loss), a GAAP measure of our operating results, to Adjusted EBITDA as defined in the Credit Agreement.

The foregoing information related to Serena’s financial results for the fiscal quarter and fiscal year ended January 31, 2011 is estimated, unaudited and subject to adjustment. Accordingly, this information should be considered forward-looking statements based on management’s current expectations of Serena’s financial results for the fiscal quarter and fiscal year ended January 31, 2011. While Serena believes these expectations are reasonable, these forward-looking statements are inherently subject to risks and uncertainties, including, but not limited to, further review by Serena’s management and audit committee of its board of directors and the results of a financial audit to be conducted by Serena’s independent registered public accounting firm. During the course of the preparation of the financial statements and related notes to the financial statements, additional items that would require material adjustments to the

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preliminary financial information presented above may be identified. Given these risks and uncertainties, Serena’s actual results may differ materially from those suggested by the forward-looking statements, and you are cautioned not to place undue reliance on these forward-looking statements. These forward-looking statements are made only as of the date hereof, and Serena does not undertake and specifically declines any obligation to publicly update or revise these forward-looking statements, whether as a result of new information, future events or developments, changed circumstances or otherwise.

Serena is furnishing the information under this Item 7.01 in this Current Report on Form 8-K to comply with Regulation FD. Such information shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section and shall not be deemed to be incorporated by reference into any of Serena’s filings under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof and regardless of any general incorporation language in such filings, except to the extent expressly set forth by specific reference in such a filing.

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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 hereunto duly authorized.

Date: February 14, 2011