Exhibit 5.1

  K&L GATES LLP 1 PARK PLAZA TWELFTH FLOOR IRVINE, CA 92614 T +1 949 253 0900    F +1 949 253 0902    klgates.com

October 22, 2018

Axonics Modulation Technologies, Inc.

26 Technology Drive

Irvine, California 92618

Ladies and Gentlemen:

We have acted as counsel to Axonics Modulation Technologies, Inc., a Delaware corporation (the “Company”), in connection with the Registration Statement on Form S-1 (File No. 333-227732) (as amended, the “Registration Statement”) filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), for the registration of 7,667,050 shares (the “Shares”) of the Company’s Common Stock, par value $0.0001 per share, which includes 1,000,050 shares subject to the underwriters’ option to purchase additional shares to cover over-allotments, if any. This opinion is being furnished to you in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

You have requested our opinion as to the matters set forth below in connection with the Registration Statement. For purposes of rendering that opinion, we have examined: (i) the Registration Statement; (ii) the most recent prospectus included in the Registration Statement on file with the Commission as of the date of this opinion letter; (iii) the form of Amended and Restated Certificate of Incorporation of the Company and the form of Amended and Restated Bylaws of the Company, each of which has been filed with the Commission as an exhibit to the Registration Statement; and (iv) the records of corporate actions of the Company relating to the Registration Statement and the authorization for issuance and sale of the Shares, and matters in connection therewith. We have also made such other investigation as we have deemed appropriate. We have examined and relied upon certificates of public officials and, as to certain matters of fact that are material to our opinion, we have also relied on a certificate of an officer of the Company. In rendering our opinion, we have also made assumptions that are customary in opinion letters of this kind. We have not verified any of those assumptions.

Our opinion set forth below is limited to the Delaware General Corporation Law.

Based upon and subject to the foregoing, it is our opinion that the Shares are duly authorized for issuance by the Company and, when issued and paid for in accordance with a definitive underwriting agreement approved by the Board of Directors of the Company, or a committee thereof, will be validly issued, fully paid and nonassessable.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the reference to this firm in the Registration Statement under the caption “Legal Matters.” In giving our 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 thereunder.

Yours truly,

/s/ K&L Gates LLP

K&L Gates LLP