An electric power steering apparatus (11) includes a reduction mechanism (G) for transmitting the rotation of a rotating shaft (28a) of a motor (28) to a ball screw nut (20) while reducing the speed of the rotation. The reduction mechanism includes a drive gear (29), which is coaxially connected to the rotating shaft of the motor, and a driven gear (16a), which is arranged on the outer surface of the ball screw nut. Due to the reduction mechanism, the motor may be inclined relative to a rack shaft (18).