An electric power steering controller adjustably generates a target steer torque dynamically by weighting (i) a load based target steer torque that is determined based on an estimated load and (ii) a steer angle based target steer torque with a weighting ratio. The weighting ratio varies depending on a condition of a road surface on which a subject vehicle is traveling, a steering state of the driver and the like, which enables an adjustment of the target steer torque to suitably accommodate the condition of the road surface and to provide a road surface conscious steering feel while achieving robustness over an influence of a friction of the mechanical components in a steering system.