A semiconductor device has: a memory element which is arranged on a semiconductor substrate and records information therein; a terminal for inputting first voltage for recording the information to the memory element and second voltage lower than the first voltage for reading out the information from the memory element; and an electrostatic discharge protection circuit which is connected to the terminal. The electrostatic discharge protection circuit includes a diode whose cathode is connected to the first terminal and whose anode is connected to a ground potential, and a first MOS transistor whose drain and gate are connected to the terminal and whose source and back gate are connected to the ground potential.