Carroll, a 6-foot-6 guard, was held out the first three games pending an ongoing review of the program.
He averaged 17.5 points and 6.6 rebounds last season and was the Big 12's leading returning scorer, the Cowboys' leading returning rebounder and a preseason All-Big 12 selection.
Oklahoma State was one of the schools impacted by the FBI investigation into bribery and corruption in college basketball. The Cowboys fired assistant coach Lamont Evans following his arrest. He allegedly solicited $22,000 from two financial advisers to steer two players to them.
ESPN's Jeff Borzello contributed to this report.