Aquinas Institute of Theology is a Catholic graduate school and seminary in St. Louis, Missouri.

Aquinas Institute is accredited by the Association of Theological Schools in the United States and Canada.

1956 - The two Dominican colleges, St. Rose of Lima and the Studium Generale, are incorporated as one, the Aquinas Institute of Philosophy and Theology.

1964 - Aquinas Institute is accredited by the North Central Association of Colleges and Secondary Schools.

1965 - The Association of Theological Schools of Iowa is formed, the first ecumenical consortium established in the country.