The John M. Olin Business School is one of seven academic schools at Washington University in St. Louis. Located alongside the School of Law and the College of Arts and Sciences on Washington University's Danforth Campus, Olin has been ranked in the "Top-Tier" (Top 30) of US MBA programs by BusinessWeek since the ranking's inception (1988), and in recent years its undergraduate program has been ranked among the top 15 in the nation by U.S. News & World Report. The John M. Olin Business School comprises Simon Hall and the Charles F. Knight Executive Education Center on the Danforth Campus.

The Business School was founded in 1917 and later was named after entrepreneur John M. Olin in 1988. As one of the leading business schools in the United States, Olin obtained its reputation from strong research-oriented achievements and competitive graduates. The Olin School is revered for its small class sizes, academically rigorous coursework, flexible curriculum and quality of its teaching faculty. The school offers BSBA, MBA, MS in Finance, Masters in Accounting, Executive MBA, and PhD degrees. In 2002, an Executive MBA program was established in Shanghai, in cooperation with Fudan University.

Students can select electives from other areas in Washington University such as the Medical School, College of Arts & Sciences, Engineering School, School of Social Work and the Law School.

Olin has a network of about 13,000 active alumni all over the world. Over the last several years, the business school’s endowment has increased to $178 million (2004) and annual gifts average $12 million per year. After a donation from John E. Simon, the 80,000 sq.ft. Simon Hall was opened in 1986.