Cherilus was the 17th pick in April's draft out of Boston College. He is expected to play right tackle for the Lions after being a left tackle in 2007.
Final details on the contract were not set, but Greg Diulus, Cherilus' agent, said an agreement was in place and could be finalized Thursday. The team opened training camp Wednesday.
Cherilus will be a focal point as the Lions try to improve their running game. He played the right side early in his career at BC, and will replace Damien Woody, who left as a free agent to join the Jets.
The Lions will take all the help they can get. Detroit surrendered 54 sacks last season and has given up an NFL-worst 117 in the last two years.
Cherilus, who was born in Haiti, stands 6-foot-6 and weighs 320 pounds. He figures to be the only new starter on the offensive line.