A four wheel steering vehicle (1), in which front wheels (2f) and rear wheels (2r) can be steered in response to a steering input from a steering wheel (11), includes a rear wheel steering control unit (50) that variably controls a rear wheel steering device such that the rear wheels are steered in a prescribed relation to a steered angle of the front wheels. When the steering input is determined while the front wheel brake and the rear wheel brake are engaged, the rear wheel steering control unit disengages the rear wheel brake and steers the rear wheels. When the fore and aft inclination angle detected by an inclination sensor (40) provided on the vehicle is greater than a threshold value, the rear wheel steering control unit prohibits a steering of the rear wheels and keeps the rear wheel brake engaged even if the steering input is determined.