Oklahoma State University–Stillwater, located in Stillwater, Oklahoma, USA, is a land-grant, sun-grant, coeducational public research university founded in 1890 under the Morrill Act. Originally known as Oklahoma Agricultural and Mechanical College (Oklahoma A&M), it is the flagship institution of the Oklahoma State University System with 32,760 students for the 2006–07 academic year. The flagship campus had a total enrollment of 23,307 students for the 2006–07 academic year. Oklahoma State is situated 62 miles west of Tulsa, and 42 miles northeast of Oklahoma City.

The Oklahoma State Cowboys have a rich athletic heritage, being the home of 48 national championships, a total better than all but 3 schools in the nation, and first in the Big 12. Academically, the Donald W. Reynolds School of Architecture ranks among the top 20 in the nation. Oklahoma State University ranks #71 among Best Value universities, receiving top-billing in the State of Oklahoma (based on in-state tuition totals), according to Kiplinger. In 1998, The Student Guide to America's 100 College Buys named OSU America's #1 Best Buy. The National Security Agency has named OSU a National Center of Academic Excellence in Information Assurance Research ("Intelligence") along with 22 other universities. The Carnegie Foundation classifies OSU as a "High Research Activity campus".