Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statementon Form S-8 (Nos. 33-54347, 33-51189 and 333-161939) of Thermo Fisher Scientific Inc.of our report dated June 16, 2022relating to the financial statements and supplemental schedulesof Thermo Fisher Scientific Inc. 401(k) Retirement Plan, which appears in this Form 11-K.

/s/PricewaterhouseCoopers LLP

Boston, Massachusetts

June 16, 2022