1990 Oklahoma State Cowboys baseball team

The 1990 Oklahoma State Cowboys baseball team represented Oklahoma State University–Stillwater in the 1990 NCAA Division I baseball season. The Cowboys played their home games at Allie P. Reynolds Stadium in Stillwater, Oklahoma. The team was coached by Gary Ward in his thirteenth season at Oklahoma State.

The Cowboys reached the College World Series, finishing as the runner up to Georgia.

The Cowboys also won the Big Eight Conference championship, the tenth in a string of sixteen consecutive conference titles which lasted until the league merged with the Southwest Conference.