An indirect longitudinal acceleration calculation section indirectly calculates longitudinal acceleration by calculating the longitudinal acceleration, which is an acceleration in a longitudinal direction of the vehicle, from change in the speed of the vehicle detected by a vehicle speed detection section. When an uphill travel detection section detects an uphill traveling state in which the vehicle is traveling on an uphill and a drive state determination section detects a no-driving-force state in which a vehicle driving force is not generated, a vehicle drawn down state detection section detects that the longitudinal acceleration indirectly calculated by the indirect longitudinal acceleration calculation section is oriented in an accelerating direction, and determines that the vehicle is in a drawn down state.