A controller of an electric power steering system includes: a basic assist component computing unit (60) that computes a first assist component (Ta1*) based on a steering torque (Th) a steered angle command value computing unit (61) that computes a steered angle command value (θt*) based on the sum of the steering torque (Th) and the first assist component (Ta1*) and a steered angle feedback controller (62) that computes a second assist component (Ta2*) through feedback control on an actual steered angle (θt). The controller further includes: a correction component computing unit (65) that computes a correction component (Tc*) based on a steering angle (θs) and an assist command value computing unit (50) that computes an assist command value (Ta*) by subtracting the correction component (Tc*) from the sum of the first assist component (Ta1*) and the second assist component (Ta2*).
