<p>A motor-driven power steering controller (ECU1) for a vehicle comprises a steering torque controlling unit (B0) for controlling a steering torque on a steering wheel (1) depending on a steering operation of the vehicle to reduce an operator's power required to operate the steering wheel (1), a braking force estimating unit (B1) for estimating braking forces to be imposed on wheels of the vehicle, a right and left braking force difference estimating unit (B2) for estimating difference between the braking forces to be imposed on the right and left wheels each estimated by the braking forces estimating unit (B1). The controller further comprises an assist steering torque providing unit (B3) for adding a counter-steering assist steering torque assisting an operator's counter-steering operation on the steering wheel to the steering torque controlled by the steering torque controlling unit (B0) in the counter-steering direction on the basis of the difference in braking force between right and left wheels estimated by the right and left brake force difference estimate unit (B2), wherein the assist steering torque providing unit prohibits providing the counter-steering assist steering torque when turning condition of the vehicle is higher than a predetermined value.</p>
