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): November 8, 2012

CareFusion Corporation

(Exact Name of Registrant as Specified in its Charter)

Delaware

(State or Other Jurisdiction of Incorporation)

3750 Torrey View Court, San Diego, California 92130

(Address of Principal Executive Offices, Including Zip Code)

(858) 617-2000

(Registrant’s Telephone Number, Including Area Code)

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 (see General Instruction A.2. below):

On November 8, 2012, CareFusion Corporation (the “Company”) issued a news release (the “News Release”) announcing preliminary selected financial results for the quarter ended September 30, 2012. In the News Release, the Company also provided an update on the status of the Company’s annual report on Form 10-K for the fiscal year ended June 30, 2012 (the “Form 10-K”). A copy of the News Release is furnished as Exhibit 99.1 to this report.

During a conference call scheduled to be held at 2:00 p.m. PST on November 8, 2012, the Company will discuss its preliminary selected financial results for the quarter ended September 30, 2012, as well as the status of the Form 10-K.

In the News Release, the Company presents non-GAAP financial measures that exclude certain amounts, including, “adjusted SG&A expenses”, “adjusted operating expenses”, and “adjusted segment profit”. Definitions of these non-GAAP financial measures, including reconciliations to the most comparable GAAP financial measures, are contained in the News Release. The Company’s management uses these non-GAAP financial measures to evaluate the Company’s performance and provides them to investors as a supplement to the Company’s reported results, as they believe this information provides additional insight into the Company’s operating performance by disregarding certain non-recurring items. These non-GAAP financial measures should not be considered in isolation, as a substitute for, or as superior to, financial measures calculated in accordance with GAAP, and the Company’s financial results calculated in accordance with GAAP and reconciliations to those financial statements should be carefully evaluated. The non-GAAP financial measures used by the Company may be calculated differently from, and therefore may not be comparable to, similarly titled measures used by other companies.

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 hereunto duly authorized.

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