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): May 9, 2013

NUCOR CORPORATION

(Exact Name of Registrant as Specified in Charter)

Delaware

(State or Other Jurisdiction of Incorporation)

Registrant’s telephone number, including area code: (704) 366-7000

N/A

(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:

(a) The Corporation held its annual meeting of stockholders on May 9, 2013.

(b) At the meeting, stockholders elected all ten of the directors nominated by the Board to serve for a term of one year and until their successors are duly elected and qualified. Each director received a greater number of votes cast “for” his or her election than votes “withheld” from his or her election as reflected below. The stockholders also ratified the appointment of PricewaterhouseCoopers LLP as the Corporation’s independent registered public accounting firm for the year ending December 31, 2013. The stockholders approved the senior officers annual and long-term incentive plans. The stockholders did not approve the amendment of Nucor’s Restated Certificate of Incorporation, the amendment of Nucor’s Bylaws, or either of the stockholder proposals presented at the meeting. For more information on the proposals, see the Corporation’s proxy statement dated March 27, 2013. The final voting results for each of the proposals presented at the meeting are set forth below.

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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.

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