The AFC West leaders used 301 passing yards from Carson Palmer to help post their first home victory in three tries. The Oakland signal-caller completed 21-of-37 passes and was intercepted once.
Michael Bush rushed 24 times for 69 yards and scored a fourth-quarter touchdown for Oakland (7-4).
Caleb Hanie made his first NFL start in place of the injured Jay Cutler for the Bears (7-4), throwing two touchdowns en route to 254 yards. But he was intercepted three times as the Bears' five-game winning streak was snapped.