Exhibit 5.1

90 SOUTH SEVENTH STREET ● SUITE 4950 ● MINNEAPOLIS, MINNESOTA 55402

TELEPHONE: +1.612.217.8800 ● JONESDAY.COM

March 15, 2024

Diebold Nixdorf, Incorporated

350 Orchard Avenue NE

North Canton, Ohio 44720-2556

Re: Registration Statement on Form S-1 Filed by Diebold Nixdorf, Incorporated

Ladies and Gentlemen:

We have acted as counsel for Diebold Nixdorf, Incorporated, a Delaware corporation (the “Company”), in connection with the registration for resale from time to time, on a continuous or delayed basis, of up to 19,511,852 shares (the “Shares”) of the Company’s common stock, $0.01 par value per share, by the selling stockholders identified in Post-Effective Amendment No. 1 to the Registration Statement on Form S-1 (as the same may be amended from time to time, the “Registration Statement”) filed by the Company to effect the registration of the Shares under the Securities Act of 1933 (the “Securities Act”) and to which this opinion has been filed as an exhibit.

In connection with the opinions expressed herein, we have examined such documents, records and matters of law as we have deemed relevant or necessary for purposes of such opinions. Based on the foregoing, and subject to the further assumptions, qualifications and limitations set forth herein, we are of the opinion that the Shares have been validly issued and are fully paid and nonassessable.

The opinions expressed herein are limited to the General Corporation Law of the State of Delaware, as currently in effect, and we express no opinion as to the effect of the laws of any other jurisdiction on the opinions expressed herein.

We hereby consent to the filing of this opinion as Exhibit 5.1 to the Registration Statement and to the reference to us under the caption “Legal Matters” in the prospectus constituting a part of the Registration Statement. In giving such consent, we do not thereby admit that we are included in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Securities and Exchange Commission promulgated thereunder.

Very truly yours,

/s/ Jones Day

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