Mayfield was chosen as Offensive Player of the Year in the annual preseason vote by a panel of media representatives who cover the Big 12.
The five Sooner selections, three on offense and two on defense, tied Texas for the most players from one school named to the team.
Joining Mayfield on the preseason All-Big 12 team are offensive tackle Orlando Brown, tight end Mark Andrews, linebacker Ogbonnia Okoronkwo and defensive back Jordan Thomas. Brown and Andrews are juniors; Mayfield, Thomas and Okoronkwo are seniors.