Exhibit 5.1

Darren DeStefano

(703) 456-8034

ddestefano@cooley.com

May 24, 2023

Luna Innovations Incorporated

301 1^st Street SW, Suite 200

Roanoke, VA 24011

We have represented Luna Innovations Incorporated, a Delaware corporation (the “Company”), in connection with the filing by the Company of a Registration Statement on Form S-8 (the “Registration Statement”) with the Securities and Exchange Commission (the “Commission”) covering the offering of up to 2,000,000 shares of the Company’s common stock, par value $0.001 per share (the “Shares”), pursuant to the Company’s 2023 Equity Incentive Plan (the “Plan”).

In connection with this opinion, we have examined and relied upon (a) the Registration Statement and the related prospectus, (b) the Company’s certificate of incorporation and bylaws, each as currently in effect, (c) the Plan, and (d) such other 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 assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, and the conformity to originals of all documents submitted to us as copies, and the due authorization, execution and delivery of all documents by all persons other than by the Company where authorization, execution and delivery are prerequisites to the effectiveness thereof. As to certain factual matters, we have relied upon a certificate of officers of the Company and have not independently verified such matters.

Our opinion is expressed only with respect to the General Corporation Law of the State of Delaware. We express no opinion to the extent that any other laws are applicable to the subject matter hereof and express no opinion and provide no assurance as to compliance with any federal or state securities law, rule or regulation.

On the basis of the foregoing, and in reliance thereon, we are of the opinion that the Shares, when sold and issued in accordance with the Plan, and the Registration Statement and the related prospectus, will be validly issued, fully paid and nonassessable (except as to shares issued pursuant to certain deferred payment arrangements, which will be fully paid and nonassessable when such deferred payments are made in full).

We consent to the filing of this opinion as an exhibit to the Registration Statement. In giving such 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 1933, as amended, or the rules and regulations of the Commission thereunder.

Sincerely,

Cooley LLP

By:	/s/ Darren DeStefano
	Darren DeStefano

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