Exhibit 5.1

March 30, 2020

Ladies and Gentlemen:

We are issuing this opinion letter in our capacity as legal counsel to Deere & Company, a Delaware corporation (the “Company”), in connection with the registration by the Company of $700,000,000 aggregate principal amount of 2.750% Notes due April 15, 2025 (the “2025 Notes”), $700,000,000 aggregate principal amount of 3.100% Notes due April 15, 2030 (the “2030 Notes”) and $850,000,000 aggregate principal amount of 3.750% Notes due April 15, 2050 (the “2050 Notes”, and together with the 2025 and 2030 Notes, the “Notes”) pursuant to the terms of the Terms Agreement, dated March 25, 2020 (the “Terms Agreement”), among the Company and BofA Securities, Inc., Citigroup Global Markets Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC, MUFG Securities Americas Inc. and RBC Capital Markets, LLC as representatives of the several underwriters named therein. The Notes are being offered and sold under a Registration Statement on Form S-3ASR (No. 333-218760) filed by the Company with the Securities and Exchange Commission (the “Commission”) on June 15, 2017 under the Securities Act of 1933, as amended (the “Securities Act”) (such Registration Statement, as amended or supplemented, is hereinafter referred to as the “Registration Statement”), including a base prospectus dated June 15, 2017 (the “Base Prospectus”), a preliminary prospectus supplement dated March 25, 2020 (the “Preliminary Prospectus Supplement”) and a final prospectus supplement dated March 25, 2020 (together with the Base Prospectus and the Preliminary Prospectus Supplement, the “Prospectus”).

In that connection, we have examined originals, or copies certified or otherwise identified to our satisfaction, of such documents, corporate records and other instruments as we have deemed necessary for the purposes of this opinion, including (i) the certificate of incorporation and by-laws of the Company, (ii) the Registration Statement and the Prospectus, (iii) the indenture, dated September 25, 2008, between the Company and The Bank of New York Mellon, as trustee (the “Indenture”) and (iv) copies of the Notes.

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Deere & Company

March 30, 2020

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For purposes of this opinion, we have assumed the authenticity of all documents submitted to us as originals, the conformity to the originals of all documents submitted to us as copies and the authenticity of the originals of all documents submitted to us as copies. We have also assumed the legal capacity of all natural persons, the genuineness of the signatures of persons signing all documents in connection with which this opinion is rendered, the authority of such persons signing on behalf of the parties thereto other than the Company and the due authorization, execution and delivery of all documents by the parties thereto other than the Company. We have not independently established or verified any facts relevant to the opinion expressed herein, but have relied upon statements and representations of officers and other representatives of the Company and others.

Our opinion expressed below is subject to the qualifications that we express no opinion as to the applicability of, compliance with, or effect of (i) any bankruptcy, insolvency, reorganization, fraudulent transfer, fraudulent conveyance, moratorium or other similar law affecting the enforcement of creditors’ rights generally, (ii) general principals of equity (regardless of whether enforcement is considered in a proceeding in equity or at law) and (iii) public policy considerations that may limit the rights of parties to obtain certain remedies.

Based upon and subject to the foregoing qualifications, assumptions and limitations and the further limitations set forth below, we are of the opinion that the Notes have been duly authorized and are binding obligations of the Company.

We hereby consent to the filing of this opinion as Exhibit 5.1 to the Company’s Current Report on Form 8-K and to its incorporation into the Registration Statement. We also consent to the reference to our firm under the heading “Legal Matters” in the Prospectus constituting part of the Registration Statement. In giving this consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act of the rules and regulations of the Securities and Exchange Commission.

We have also assumed that the execution and delivery of the Indenture and the Notes and the performance by the Company of its obligations thereunder do not and will not violate, conflict with or constitute a default under any agreement or instrument to which the Company is bound.

Our advice on every legal issue addressed in this letter is based exclusively on the internal law of the State of New York and the General Corporation Law of the State of Delaware. We do not find it necessary for purposes of this opinion, and accordingly we do not purport to cover herein, the application of the securities or “blue sky” laws of the various states to the sale of the Notes.

Deere & Company

March 30, 2020

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This opinion is limited to the specific issues addressed herein, and no opinion may be inferred or implied beyond that expressly stated herein. This opinion speaks only as of the date hereof, and we assume no obligation to revise or supplement this opinion. This opinion is furnished to you in connection with the filing of the Company’s Current Report on Form 8-K, which is incorporated into the Registration Statement, and in accordance with the requirements of Item 601(b)(5) of Regulation S-K promulgated under the Securities Act, and is not to be used, circulated, quoted or otherwise relied upon for any other purposes.