Hanna was the second consecutive offensive player taken by the Cowboys on Saturday after they used their first four selections on defensive players.
Hanna is from Flower Mound, which is only a few miles from the Cowboys' practice facility. He was picked 186th overall.
Hanna had 27 catches for 381 yards and two touchdowns last season for the Sooners. In 2010, seven of his 18 catches were for touchdowns.