Saint Louis University (SLU) is a private, co-educational Roman Catholic university in the United States. Located in St. Louis, Missouri, it was founded in 1818 as Saint Louis Academy by the Society of Jesus. Saint Louis University is one of 28 member institutions of the Association of Jesuit Colleges and Universities. The first M.D. degree awarded west of the Mississippi was conferred by Saint Louis University in 1836.

During the early 1940s, many local priests, especially the Jesuits, began to challenge the segregationist policies at the city's Catholic colleges and parochial schools. Saint Louis University opened its doors to African Americans in 1943 after its president, Father Patrick Holloran, secured the reluctant approval of St. Louis Archbishop John J. Glennon.

For over thirty years the university has maintained a campus in Madrid, Spain with a student body of around 1000.

Gene Kranz is a former NASA flight director graduated in 1954