Palmer, in his seventh year, hit on 20-of-24 passes for 233 yards. Two of the scoring throws went to Chad Ochocinco and four of them came in the first half while the Bengals were roaring to a 31-3 lead.
Cincinnati running back Cedric Benson, playing against the team that let him go after three seasons, rushed for 189 yards on 37 carries.
Cincinnati maintained a share of the lead with Pittsburgh in the AFC North at 5-2. Chicago lost its second in a row and slipped to 3-3.
Palmer drove the Bengals 77 yards the first time they had the ball and found Chris Henry with a 9-yard touchdown throw. He hit Ochocinco with an 8-yarder later in the first period, and then hooked up with J.P. Foschi for 3 yards and Laveranues Coles for 8 yards in the second period.
Palmer's final touchdown pass went to Ochocinco for 13 yards in the third period. Benson scored on a 1-yard run on the first play of the fourth quarter.
Chicago quarterback Jay Cutler threw three interceptions and the Bears also lost a fumble.
Copyright 2009 by United Press International.