Exhibit 5.1

August 29, 2025

Board of Directors

Nuburu, Inc.

7442 S Tucson Way, Suite 130

Centennial, CO 80112

Ladies and Gentlemen:

We have acted as counsel to Nuburu, Inc. (the “Company”), a Delaware corporation, in connection with the filing of the Registration Statement on Form S-1 (the “Registration Statement”) with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”). The Registration Statement relates to the resale by the selling stockholders named therein of up to 25,938,157 shares (the “Resale Shares”) of the Company’s common stock, par value $0.0001 per share (the “Common Stock”), consisting of:

(i) 20,055,588 shares of Common Stock (the “Indigo Shares”) issuable to Indigo Capital LP upon the conversion of the following promissory notes (the “Indigo Notes”): (a) a promissory note in the aggregate principal amount of $1,578,495 issued on March 3, 2025, (b) a promissory note in the aggregate principal amount of $894,708 issued on March 3, 2025, (c) a promissory note in the aggregate principal amount of $1,421,053 issued on April 22, 2025, (d) a promissory note in the aggregate principal amount of $2,108,523 issued on April 22, 2025, (e) a promissory note in the aggregate principal amount of $150,000 issued on July 16, 2025, and (f) a promissory note in the aggregate principal amount of $225,000 issued on August 18, 2025;

(ii) 672,881 shares of Common Stock (the “BL Shares”) issuable to Brick Lane Capital Management Limited upon the conversion of a promissory note (the “BL Note”) in the aggregate principal amount of $250,000 issued on June 3, 2025;

(iii) 1,562,500 shares of Common Stock (the “Bomore Shares”) issuable to Bomore Opportunity Group Ltd issuable to Bomore upon the conversion of a promissory note (the “Bomore Note”) in the aggregate principal amount of $250,000 issued on June 18, 2025;

(iv) 781,250 shares of Common Stock (the “Torcross Shares”) issuable to Torcross Capital LLC upon conversion of a promissory note (the “Torcross Note”) in the aggregate principal amount of $100,000 issued on June 25, 2025;

(v) 2,405,044 shares of Common Stock (the “Diagonal Shares”) issuable to 1800 Diagonal Lending LLC upon conversion of the following promissory notes (the “Diagonal Notes”): (a) promissory note in the aggregate principal amount of $227,700 issued on May 13, 2025, and (b) a promissory note in the aggregate principal amount of $172,700 issued on July 21, 2025; and

(vi) 460,894 shares of Common Stock (the “Boot Shares”) issuable to Boot Capital LLC upon conversion of a promissory note (the “Boot Note”) in the aggregate principal amount of $110,000 issued on May 13, 2025.

This opinion letter is furnished to you at your request to enable you to fulfill the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act in connection with the Registration Statement, and no opinion is expressed or may be implied herein as to any matter pertaining to the contents of the Registration Statement other than as to the valid issuance of the Resale Shares.

As the basis for the opinion hereinafter expressed, we have reviewed originals or copies of the following:

A. an executed copy of the Registration Statement and the related prospectuses;

B. the Amended and Restated Certificate of Incorporation of the Company, as amended, as currently in effect;

C. the Amended and Restated Bylaws of the Company, as amended, and as currently in effect;

D. the Indigo Notes, BL Note, Bomore Note, Torcross Note, Diagonal Notes, and Boot Note (the “Transaction Documents”);

E. a certificate of good standing covering the Company, issued by the Secretary of State of the State of Delaware as of a recent date (the “Good Standing Certificate”); and

F. such resolutions, records, documents, certificates, memoranda and other instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below.

We have relied upon the foregoing and upon certificates and other assurances of officers of the Company and others as to factual matters without having independently verified such factual matters. We have assumed for purposes of this opinion: (a) information contained in documents reviewed by us is true, complete and correct; (b) the genuineness and authenticity of all signatures on original documents; (c) the accuracy and completeness of all documents delivered to us and the authenticity of all documents submitted to us as originals; (d) the conformity to originals of all documents submitted to us as copies; (e) the accuracy, completeness and authenticity of certificates of public officials; (f) the legal capacity of all natural persons; and (g) the due authorization, execution and delivery of all documents by parties other than the Company.

We are opining herein as to the Delaware General Corporation Law, as amended, and we express no opinion with respect to the applicability thereto, or the effect thereon, of the laws of any other jurisdiction, or as to any matters of municipal law or the laws of any local agencies within any state.

Based on the foregoing, and subject to the qualifications, assumptions and limitations stated herein, we are of the opinion that each of the Resale Shares, when issued in accordance with the terms of the Transaction Documents applicable to such Resale Share, will be validly issued, fully paid and nonassessable.

The foregoing opinions are qualified to the extent that the enforceability of any document or instrument may be limited by or subject to bankruptcy, insolvency, fraudulent transfer or conveyance, reorganization, moratorium or other similar laws relating to or affecting creditors’ rights generally, and general equitable or public policy principles.

We expressly disavow any obligation to advise you with respect to future changes in law or in our knowledge or as to any event or change of condition occurring subsequent to the date of this letter. This opinion is for your benefit in connection with the Registration Statement and may be relied upon by you and by persons entitled to rely upon it pursuant to the applicable provisions of the Securities Act.

We consent to the filing of this opinion as Exhibit 5.1 to the Registration Statement. We also consent to the reference to our firm under the heading “Legal Matters” in the Registration Statement. In giving these consents, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission.

Sincerely,

/s/ Holland & Hart LLP