Embodiments of the present invention are directed to provide an internal voltage generator of a semiconductor memory device for generating a predetermined stable level of an internal voltage. The semiconductor memory device includes a control signal generator, an internal voltage generator and an internal voltage compensator. The control signal generator generates a reference signal and a compensating signal which are corresponding to voltage level of the reference signal. The internal voltage generator generates an internal voltage in response to the reference signal. The internal voltage compensator compensates the internal voltage in response to the compensating signal.