In a driving support system of a vehicle, there is provided a structure that, even during operating a control based on a machine input, a driver's sense of incongruity can be reduced as much as possible and/or the steering of the driver be can reflected. The vehicle is equipped with a steering assist mechanism and a braking-driving force distribution mechanism of right and left wheels. In operations of the inventive device, a steering assist torque, applied by the steering assist mechanism, is controlled to a target value determined with reference to a target steering torque to achieve the target route, determined without depending on steering of a driver, and a driver's steering torque; and a braking-driving force difference between the right and left wheels is controlled to a target value based on a steering angle of the driver.