An air flow rate control apparatus for an internal combustion engine includes a stepping motor. The stepping motor has a plurality of coils and a rotor which is rotated by energizing the coils. A throttle valve connected to the rotor moves together with the rotor, and controls a rate of air flow drawn into the internal combustion engine. A control device is operative for feeding command currents of first and second command current values to first and second coils among the plurality of the coils respectively, and for controlling a degree of opening of the throttle valve. The first and second command current values correspond to a command degree of opening of the throttle valve at which the control device is intended to control the throttle valve. A direction of a resultant of vector forces generated by the first and second command currents simultaneously fed to the first and second coils corresponds to a held position of the rotor. A magnitude of the resultant of the vector forces corresponds to a magnitude of a hold force of the rotor.