Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statements on Forms S-3 (File Nos. 333-208870) and on Form S-8 (File Nos. 333-197498, 333-204549, 333-209831 and 333-216202) of Sage Therapeutics, Inc. of our report dated February 22, 2018 relating to the financial statements and the effectiveness of internal control over financial reporting, which appears in this Form 10-K.

/s/ PricewaterhouseCoopers LLP

Boston, MA

February 22, 2018