A cruise control system is configured to cancel/prohibit cruise control depending on the operating state of the wipers. When the wipers are in a continuous operation mode and low speed following cruise control is in progress, execution of the low speed following cruise control is continued. When the wipers are in a continuous operation mode and high speed following cruise control is in progress, execution of the high speed following cruise control is continued if the vehicle speed is in the vehicle speed overlap region or if a preceding vehicle is detected (i.e., even if the vehicle speed is not in the vehicle speed overlap region). When the wipers are in a continuous operation mode and high speed following cruise control is in progress, the high speed following cruise control is canceled if the vehicle speed exceeds the vehicle speed overlap region and a preceding vehicle is not detected.