Abstract: A control method of controlling an electric rotating machine for vehicle includes an electric rotating machine 1 comprised of a rotator having a field winding 5 and a stator having an armature winding 3, a field current controller 9 for controlling a field current supplied from a direct-current power supply to the field winding 5, and a power converter 6 for converting a direct-current power into an alternating-current power and applying the power to the armature winding 3. When the field current controller 9 starts to supply a current to the field winding 5 for starting an internal combustion engine, the power converter 6 supplies a power to the armature winding 3 so that magnetic flux in a direction opposite to that generated by the field winding 5 is generated simultaneously with or immediately before starting the power supply.