The 6-foot-1, 208-pound wide receiver was selected No. 68 out of Ohio State. He ranked seventh in school history in career receptions (136) and eighth in yards receiving (1,955).
Houston has signed seven of its eight draft picks. Only third-round pick Brandon Brooks, a 6-4, 353-pound offensive lineman from Miami (Ohio), remains unsigned.
Posey, had five career 100-yard receiving games at Ohio State, including three during his junior season. He earned All-Big Ten honorable mention as a junior after starting all 13 games and finishing second on the team with 53 receptions for 848 yards and seven touchdowns. Posey was suspended for 10 games as a senior in the wake of the memorabilia-for-cash scandal at the school.