Simmons University (previously Simmons College) is a private university in Boston, Massachusetts, United States. It was established in 1899 by clothing manufacturer John Simmons. In 2018, it reorganized its structure and changed its name to a university. Its undergraduate program is women-focused while its graduate programs are co-educational.

Simmons is accredited by the New England Commission of Higher Education. In 2020, it accepted 83 percent of applicants for undergraduate admission. The university is divided into two campuses in the Fenway-Kenmore neighborhood totaling 12 acres (4.9 ha), one of which has five academic buildings and the other of which has nine Georgian-style residential buildings.

As of fall 2025, the university enrolled 1,675 undergraduates and 3,673 graduate students. Its athletics teams compete in NCAA Division III as the Sharks.