A method of controlling servo motor by using a simply constructed motor current controller to take out a large output from the servo motor while protecting the switching elements of the controller from over currents. Integration elements (9,9') integrate deviations between an instruction current (ir) that flows into a plurality of windings that constitute armature windings of each of the phases and currents (la, Ib) that flow into said windings. The currents (la, Ib) are amplified through proportional elements (10, 10') and are controlled substantially independently from each other so as to assume an equal value by a PWM control unit (3) which operates in response to a control signal obtained by adding up together the outputs from the elements (9 to 10').