<Page> Exhibit 23.1 CONSENT OF INDEPENDENT ACCOUNTANTS We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (Nos. 333-49852, 333-49856, 333-97523 and 333-97527) of Dyax Corp. of our report dated March 19, 2003, relating to the financial statements and financial statement schedule, which appears in this Form 10-K. /s/ PricewaterhouseCoopers LLP Boston, Massachusetts March 27, 2003