A semiconductor device comprises: a signal of high voltage not less than the power voltage; a first transistor for transmitting the high voltage signal; a second transistor for electrically charging and discharging the gate potential of the first transistor; and a circuit for generating a pulse signal of which "H" level is a voltage higher than the power voltage by the threshold voltage of the second transistor. The pulse signal generating circuit is connected to the gate electrode of the second transistor. This cancels the drop of a voltage corresponding to the threshold voltage generated at the time when the electric charge is transferred to the gate electrode of the first transistor. Accordingly, even though the power voltage is low, a high voltage signal can be transferred through the first transistor and the word line potential can be boosted to a voltage not less than the power voltage.