A vehicle AC generator control apparatus, the rotor of an vehicle AC generator 1 of which is coupled through a torque transfer member with the output axle of an internal combustion engine mounted in a vehicle, is provided with a magnetic-field current control system that can control the value c of a magnetic-field current flowing in a magnetic-field winding 3 of the vehicle AC generator 1 so that the magnetic-field current value c coincides with a magnetic-field current command value b; it is made possible to make the rotation torque of the vehicle AC generator 1 depend only on the rotation speed and to stabilize control of the internal combustion engine.