A level shift circuit for sustaining the activation and inactivation response of a transistor with respect to an input signal in a preferable manner. The level shift circuit includes a shift circuit for converting an input signal having a first voltage to an output signal having a second voltage that is higher than the first voltage. The voltage generation circuit includes a control voltage generation circuit, for generating control voltage having a generally constant voltage level irrespective of the level of a power supply voltage, and a bias generation circuit. The bias generation circuit generates bias voltage so that the node voltage of the shift circuit is substantially equalized with the control voltage.