Clark University is a private research university in Worcester, Massachusetts, United States. Founded in 1887 with a large endowment from its namesake Jonas Gilman Clark, a prominent businessman, Clark was one of the first modern research universities in the United States. Originally an all-graduate institution, Clark's first undergraduates entered in 1902 and women were first enrolled in 1942.

The university offers 46 majors, minors, and concentrations in the humanities, social sciences, natural sciences, and engineering and allows students to design specialized majors and engage in pre-professional programs. It is a member of the Higher Education Consortium of Central Massachusetts, which enables students to cross-register at other Worcester institutions including the Worcester Polytechnic Institute and the College of the Holy Cross.

Clark is classified among "R2: Doctoral Universities – High research activity". It was a founding member of the Association of American Universities, but departed in 1999. The university competes intercollegiately in 17 NCAA Division III varsity sports as the Clark Cougars and is a part of the New England Women's and Men's Athletic Conference. Clark faculty, alumni, and affiliates have included business executives and inventors of the wind chill factor and the birth control pill.