Abstract: An electric power steering system includes an electric actuator, a current indication value generation unit, an actuator control unit, and a noise signal generation unit. The electric actuator is configured to apply assist force to a steering device. The steering device is configured to turn a steering wheel of a vehicle. The current indication value generation unit is configured to generate a current indication value in accordance with a target value of the assist force. The actuator control unit is configured to supply electric power to the electric actuator in accordance with the current indication value. The noise signal generation unit is configured to add a noise signal to the current indication value. The noise signal has a dominant frequency that is a frequency matching a control clock frequency of the vehicle or a harmonic component of the control clock frequency.