Thurman missed the 2006 season for violating the NFL Substance Abuse Policy and was denied reinstatement for 2007. The NFL cleared Thurman to train and work out at the Bengals' facilities in January.
"Odell has met the NFL's conditions for reinstatement and has been added to our off-season roster," Bengals Coach Marvin Lewis said. "It is now up to Odell to continue to meet all NFL guidelines, and to maintain a standard of personal responsibility that will allow him the chance to compete for a spot on our team."
Thurman led the Bengals in tackles as a rookie in 2005. He received a four-game suspension to begin the 2006 season for the substance abuse violation. Following a drunken driving arrest in September 2006, the NFL extended the suspension for the full season.