Exhibit 5.1

		Richard L. Mack Executive Vice President, General Counsel and Corporate Secretary The Mosaic Company 3033 Campus Drive, Suite E490 Plymouth, MN 55441 www.mosaicco.com		Telephone: (763) 577-2851 Facsimile: (763) 577-2990   Writer’s Direct Dial: (763) 577-2851 E-Mail: Richard.Mack@mosaicco.com

November 13, 2013

The Mosaic Company

3033 Campus Drive, Suite E490

Plymouth, MN 55441.

Ladies and Gentlemen:

I am the Executive Vice President, General Counsel and Corporate Secretary of The Mosaic Company, a Delaware corporation (the “Company”) and in such capacity have acted as counsel to the Company in connection with the preparation and filing with the Securities and Exchange Commission (the “Commission”) of a prospectus supplement dated November 7, 2013 (the “Prospectus Supplement”) to the Prospectus dated October 12, 2011 relating to the registration statement on Form S-3 (the “Registration Statement”) filed by the Company with the Commission under the Securities Act of 1933, as amended (the “Securities Act”), with regard to the offer and sale by the Company of $900,000,000 of the Company’s 4.250% Senior Notes due 2023 (the “2023 Notes”), $500,000,000 of the Company’s 5.450% Senior Notes due 2033 (the “2033 Notes”) and $600,000,000 of the Company’s 5.625% Senior Notes due 2043 (the “2043 Notes” and, together with the 2023 Notes and the 2033 Notes, the “Offered Securities”) pursuant to the Underwriting Agreement dated November 7, 2013 (the “Underwriting Agreement”) among the Company and Goldman, Sachs & Co., J.P. Morgan Securities LLC, Morgan Stanley & Co. LLC and Wells Fargo Securities, LLC, as representatives of the several underwriters named in Schedule A thereto. The Offered Securities are to be issued pursuant to the Indenture, dated as of October 24, 2011, between the Company and U.S. Bank National Association, as trustee.

I have examined the Registration Statement and the Prospectus Supplement and I, or attorneys acting under my supervision, also have examined the originals, or duplicates or certified or conformed copies, of such corporate and other records, agreements, documents and other instruments and have made such other investigations as I have deemed relevant and necessary in connection with the opinion hereinafter set forth. As to questions of fact material to this opinion, I have relied upon certificates or comparable documents of public officials.

In rendering the opinion set forth below, I have assumed the genuineness of all signatures, the legal capacity of natural persons, the authenticity of all documents submitted to me as originals, the conformity to original documents of all documents submitted to me as duplicates or certified or conformed copies and the authenticity of the originals of such latter documents.

Based on the foregoing, I am of the opinion that the Offered Securities constitute binding obligations of the Company.

The Mosaic Company

November 13, 2013

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The opinion set forth above is subject to the following qualifications and exceptions:

I do not express any opinion herein concerning any laws other than the Delaware General Corporation Law (including the statutory provisions, all applicable provisions of the Delaware Constitution and reported judicial decisions interpreting the foregoing), and the laws of the State of New York (excluding state blue sky securities law matters).

The Mosaic Company

November 13, 2013

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I hereby consent to the filing of this opinion as an exhibit to the Company’s Current Report on Form 8-K to be filed with the Commission on or about November 13, 2013, which Form 8-K will be incorporated by reference into the Registration Statement, and to the reference to the use of my name under the caption “Legal Matters” contained in the prospectus constituting part of the Registration Statement. In giving such consent, I do not thereby admit that I am in the category of persons whose consent is required under Section 7 of the Securities Act.