A vehicular control system includes a forward-viewing camera viewing through the windshield at least forward of the equipped vehicle, a left-side camera viewing at least sideward and rearward of the equipped vehicle, a right-side camera viewing at least sideward and rearward of the equipped vehicle, and an electronic control unit (ECU). Image data captured by the cameras is transferred to and is processed at the ECU. Responsive at least in part to processing at the ECU of transferred image data, the vehicular control system detects another vehicle present rearward of the equipped vehicle and approaching the equipped vehicle in the same traffic lane that the equipped vehicle is traveling in on the road the equipped vehicle is traveling along. The vehicular control system undertakes a pre-impact measure to prepare the equipped vehicle for impact by the other vehicle and/or controls the equipped vehicle to mitigate impact by the other vehicle.