Exhibit 5.1

1345 AVENUE OF THE AMERICAS, 11^th FLOOR NEW YORK, NEW YORK 10105 TELEPHONE: (212) 370-1300 FACSIMILE: (212) 370-7889 www.egsllp.com

July 2, 2020

BioLife Solutions, Inc.

3303 Monte Villa Parkway

Bothell, WA 98021

Re: Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel to BioLife Solutions, Inc., a Delaware corporation (the “Company”), in connection with the preparation an filing with the Securities and Exchange Commission (the “Commission”) of a registration statement on Form S-3 (the “Registration Statement”) pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Securities Act”), for the registration of shares of Common Stock, $0.001 par value per share, of the Company (the “Common Stock”), with a proposed maximum aggregate offering price of $11,293,125 (the “Shares”), including shares of Common Stock issuable upon exercise of an option granted to the underwriters by the Company to purchase additional shares.

The Shares are to be sold by the Company pursuant to an underwriting agreement, dated July 2, 2020 (the “Underwriting Agreement”), entered into by and between the Company and Cowen and Company, LLC, Oppenheimer & Co. Inc. and Stephens Inc., as representatives of the several underwriters named in the Underwriting Agreement, which will be filed on a Current Report on Form 8-K.

We are acting as counsel for the Company in connection with the issue and sale by the Company of the Shares. We have examined and relied upon signed copies of the Registration Statement as filed with the Commission. We have also examined and relied upon the Underwriting Agreement, minutes of meetings and actions of the stockholders and the Board of Directors of the Company as provided to us by the Company, the Certificate of Incorporation and Bylaws of the Company, each as restated and/or amended to date, and such other documents as we have deemed necessary for purposes of rendering the opinions hereinafter set forth.

In our examination of the foregoing documents, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as copies, the authenticity of the originals of such latter documents and the legal competence of all signatories to such documents.

Our opinions set forth below are qualified to the extent that they may be subject to or affected by (i) applicable bankruptcy, insolvency, reorganization, receivership, moratorium, fraudulent transfer, fraudulent conveyance or similar laws relating to or affecting the rights or remedies of creditors generally, (ii) statutory or decisional law concerning recourse by creditors to security in the absence of notice or hearing, (iii) duties and standards imposed on creditors and parties to contracts, including, without limitation, requirements of good faith, reasonableness and fair dealing, and (iv) general equitable principles. We express no opinion as to the availability of any equitable or specific remedy upon any breach of any of the agreements as to which we are opining herein, or any of the agreements, documents or obligations referred to therein, or to the successful assertion of any equitable defenses, inasmuch as the availability of such remedies or the success of any equitable defense may be subject to the discretion of a court.

We also express no opinion herein as to any provision of any agreement (a) which may be deemed to or construed to waive any right of the Company, (b) to the effect that rights and remedies are not exclusive, that every right or remedy is cumulative and may be exercised in addition to or with any other right or remedy and does not preclude recourse to one or more other rights or remedies, (c) which is in violation of public policy, including, without limitation, any provision relating to indemnification and contribution with respect to securities law matters, or (d) relating to choice of law or consent to jurisdiction.

We also express no opinion herein as to the laws of any state or jurisdiction other than the General Corporation Law of the State of Delaware, the state laws of the State of New York and the federal laws of the United States of America.

Based upon and subject to the foregoing, we are of the opinion that the Shares have been duly authorized for issuance and, when such Shares are issued and paid for in accordance with the terms and conditions of the Underwriting Agreement, such Shares will be validly issued, fully paid and nonassessable.

Please note that we are opining only as to the matters expressly set forth herein, and no opinion should be inferred as to any other matters. This opinion is based upon currently existing statutes, rules, regulations and judicial decisions, and we disclaim any obligation to advise you of any change in any of these sources of law or subsequent legal or factual developments which might affect any matters or opinions set forth herein.

We hereby consent to the filing of this opinion with the Commission as an exhibit to the Registration Statement in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act and to the use of our name therein and in the related Prospectus under the caption “Legal Matters.” In giving such consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission.

Yours truly,

/s/ Ellenoff Grossman & Schole LLP

Ellenoff Grossman & Schole LLP