Exhibit 5.1

[HAYNES AND BOONE, LLP LETTERHEAD]

March 22, 2019

BioSig Technologies, Inc.

12424 Wilshire Blvd., Suite 745

Los Angeles, CA 90025

Ladies and Gentlemen:

We have acted as counsel for BioSig Technologies, Inc., a Delaware corporation (the “Company”), in connection with the filing with the Securities and Exchange Commission (the “Commission”) on the date hereof, under the Securities Act of 1933, as amended (the “Act”) of a registration statement on Form S-3 (the “Registration Statement”) by the Company relating to (i) shares of common stock, $0.001 par value per share, of the Company (the “Common Stock”), (ii) preferred stock, $0.001 par value per share, of the Company (the “Preferred Stock”), (iii) warrants to purchase Common Stock or Preferred Stock (the “Warrants”), and (iv) units comprised of one or more shares of Common Stock, Preferred Stock or Warrants in any combination (the “Units” and, together with the Common Stock, the Preferred Stock and the Warrants, the “Securities” and individually a “Security”) that may be issued and sold from time to time pursuant to Rule 415 under the Act for an aggregate initial offering price not to exceed $75,000,000.

For purposes of the opinions we express below, we have examined originals, or copies certified or otherwise identified, of (i) the certificate of incorporation and bylaws, each as amended to date, of the Company (the “Charter Documents”); (ii) the Registration Statement and all exhibits thereto; (iii) the specimen Common Stock certificate of the Company and (iv) such other corporate records of the Company as we have deemed necessary or appropriate for purposes of the opinions hereafter expressed.

As to questions of fact material to the opinions expressed below, we have, without independent verification of their accuracy, relied to the extent we deem reasonably appropriate upon the representations and warranties of the Company contained in such documents, records, certificates, instruments or representations furnished or made available to us by the Company.

In making the foregoing examination, we have assumed (i) the genuineness of all signatures, (ii) the authenticity of all documents submitted to us as originals, (iii) the conformity to original documents of all documents submitted to us as certified or photostatic copies, (iv) that all agreement or instruments we have examined are the valid, binding and enforceable obligations of the parties thereto, and (v) that all factual information on which we have relied was accurate and complete.

We have also assumed that (i) the Company will continue to be incorporated and in existence and good standing in its jurisdiction of organization, (ii) the Registration Statement, and any amendments thereto (including post-effective amendments), will have become effective; (iii) no stop order of the Commission preventing or suspending the use of the prospectus contained in the Registration Statement or any prospectus supplement will have been issued; (iv) a prospectus supplement will have been prepared and filed with the Commission properly describing the Securities offered thereby and will have been delivered to the purchaser(s) of the Securities as required in accordance with applicable law; (v) all Securities will be offered, issued and sold in compliance with applicable federal and state securities laws and in the manner stated in the Registration Statement and the appropriate prospectus supplement; (vi) a definitive purchase, underwriting or similar agreement with respect to any Securities offered will have been duly authorized and validly executed and delivered by the Company and the other parties thereto and will be an enforceable obligation of the parties thereto; (vii) in connection with the sale of Warrants, any required warrant agreement or agreement relating to the Warrants (a “Warrant Agreement”) will have been executed and delivered by all applicable parties and will be enforceable in all respects in accordance with its terms; (viii) in connection with the sale of any Units, any required unit agreement relating to the Units (a “Unit Agreement”) will have been executed and delivered by all applicable parties and will be enforceable in all respects

BioSig Technologies, Inc.

March 22, 2019

Page 2

in accordance with its terms; (ix) any securities issuable upon conversion, exchange, redemption or exercise of any Securities being offered will be duly and validly authorized, created and, if appropriate, reserved for issuance upon such conversion, exchange, redemption or exercise; and (x) with respect to shares of Common Stock or Preferred Stock offered or underlying the Securities offered, there will be sufficient shares of Common Stock or Preferred Stock authorized under the Charter Documents and not otherwise reserved for issuance.

Based on the foregoing, and subject to the limitations and qualifications set forth herein, we are of the opinion that:

BioSig Technologies, Inc.

March 22, 2019

Page 3

consideration therefor provided for therein (which shall not be less than the par value of any Common Stock or Preferred Stock underlying such Warrants), all in accordance with the Registration Statement and any prospectus supplement, the Warrants will constitute valid and legally binding obligations of the Company. 

The opinions set forth above are subject to the following qualifications, limitations and exceptions:

(a) The opinions are subject to (i) the effect of any applicable bankruptcy, insolvency, reorganization, moratorium, rearrangement, liquidation, conservatorship or other similar laws now or hereafter in effect relating to or affecting the rights of creditors generally, (ii) provisions of applicable law pertaining to the voidability of preferential or fraudulent transfers and conveyances and (iii) the fact that the remedy of specific performance and injunctive and other forms of equitable relief may be subject to equitable defenses and to the discretion of the court before which any proceeding therefor may be brought.

(b) The opinions are subject to the effect of (i) general principles of equity, including (without limitation) concepts of materiality, reasonableness, good faith and fair dealing, general matters of public policy and other similar doctrines generally affecting the enforceability of agreements (regardless of whether considered in a proceeding in equity or at law) (ii) obligations of good faith and fair dealing under New York law, and (iii) other commonly-recognized statutory and judicial constraints on enforceability, including statutes of limitation, limitations on rights to indemnification that contravene law or public policy and the effectiveness of waivers of rights or benefits that cannot be effectively waived under applicable law.

(c) In rendering the opinions, we have assumed that, at the time of the sale of the Securities, (i) the resolutions of the Board of Directors or similar governing body, as reflected in the minutes and proceedings of the Company, will not have been modified or rescinded and (ii) there will not have occurred any change in the laws affecting the authorization, execution, delivery, issuance, sale, ranking, validity or enforceability of the Securities.

The opinions expressed herein are limited to the federal laws of the United States of America, and, to the extent relevant to the opinions expressed herein, (i) the Delaware General Corporation Law and (ii) the laws of the State of New York, in each case as in effect on the date hereof (all of the foregoing being referred to as the “Opined on Law”). We do not express any opinion with respect to any other laws, or the laws of any other jurisdiction (including, without limitation, any laws of any other jurisdiction which might be referenced by the choice-of-law rules of the Opined Law), other than the Opined on Law or as to the effect of any such other laws on the opinions herein stated.

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

Very truly yours,

/s/ Haynes and Boone, LLP