Petrino made the announcement after Monday's first practice of fall camp. He did not elaborate, but the Courier-Journal reported Williams' dismissal is due to his being charged on June 23 with felony theft for allegedly stealing money from his teammates' bank accounts.
Listed No. 2 at one tackle spot on the Cardinals' depth chart, the 6-foot-1, 292-pound Williams was one of the more experienced linemen returning this season.
The Atlanta native had 29 tackles with a sack, 5-plus tackles for loss and two fumble recoveries in 11 games last season after transferring from Northwest Mississippi Junior College.
The Associated Press contributed to this report.