Exhibit 5.1

February 5, 2018

Haemonetics Corporation

400 Wood Road
Braintree, MA 02184

Re: Registration Statement on Form S-8 Relating to the 2007 Employee Stock Purchase Plan (the “Plan”) of Haemonetics Corporation, a Massachusetts corporation (the “Company”)

Dear Sir or Madam:

Reference is made to the above-captioned Registration Statement on Form S-8 (the “Registration Statement”) filed by the Company on the date hereof with the Securities and Exchange Commission under the Securities Act of 1933, as amended, relating to the registration of 1,800,000 shares of common stock, par value $.01 per share, of the Company issuable pursuant to the Plan (the “Shares”).

We have examined, and are familiar with, and have relied as to factual matters solely upon, a copy of the Plan, the Company’s amended and restated articles of organization, as amended, the by-laws of the Company, as amended, the minute books and stock records of the Company and originals of such other documents, certificates and proceedings as we have deemed necessary for the purpose of rendering this opinion.

Based on the foregoing, we are of the opinion that the Shares have been duly authorized and, when issued in accordance with the terms of the Plan, will be legally issued, fully paid and nonassessable.

This opinion is limited to the laws of The Commonwealth of Massachusetts, and we render no opinion with respect to the laws of any other jurisdiction.

We hereby consent to the filing of this opinion as Exhibit 5.1 to the Registration Statement and to the use of our name in the Registration Statement under the caption “Legal Matters” in the prospectuses included as a part thereof. In giving this consent, we do not 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 Securities and Exchange Commission thereunder.

Very truly yours,

/s/ Choate, Hall & Stewart LLP

CHOATE, HALL & STEWART LLP