Baker Mayfield led the way as the Browns opened up a 25-0 first-half lead and cruised past the Lions 35-17 in their preseason finale in Detroit.
Mayfield threw for 138 yards and Nate Orchard took an interception 64 yards for a score in the winning effort.
The Browns finished the preseason 3-and-1.
The Browns now turn their attention to the start of the regular season.
They host the Steelers in their Week One opener next Sunday at FirstEnergy Stadium.
The Browns finished last season 0-and-16 and have just one win in their last 32 regular-season games.