The 2003 Oklahoma State Cowboys football team represented Oklahoma State University as a member of the Big 12 Conference during the 2003 NCAA Division I-A football season. Led by third-year head coach Les Miles, the Cowboys compiled an overall record of 9–4 with a mark of 5–3 in conference play, placing third in the Big 12's South Division. Oklahoma State was invited to the Cotton Bowl Classic, where the Cowboys lost to the Ole Miss. The team played home games at Boone Pickens Stadium in Stillwater, Oklahoma.