A voltage level conversion circuit for converting a voltage level of a low voltage system input signal into a voltage level of a high voltage system signal comprises a latch circuit comprising plural high-breakdown-voltage MOS transistors having a high power supply voltage as a breakdown voltage, a first high-breakdown-voltage N channel MOS transistor which discharges one of latch nodes of the latch circuit, and a second high-breakdown-voltage N channel MOS transistor which discharges the other latch node, and a pulse signal obtained by boosting a low voltage system pulse signal is applied to a gate of the first or second high-breakdown voltage N channel MOS transistor when the input signal transits.