A semiconductor device comprising: an electrostatic protection circuit; and a MOSFET including a gate terminal, wherein the electrostatic protection circuit includes a positive-side first power supply terminal, a negative-side second power supply terminal, a first protection diode including a first cathode terminal electrically connected to the first power supply terminal and a first anode terminal electrically connected to the gate terminal, a second protection diode including a second anode terminal electrically connected to the second power supply terminal via a first resistance element, and a second cathode terminal electrically connected to the gate terminal, and a bipolar transistor including a base terminal, an emitter terminal, and a collector terminal, wherein the first protection diode, the second protection diode, the bipolar transistor, and the first resistance element are respectively formed on a semiconductor substrate made of silicon carbide, the bipolar transistor is electrically connected to the second anode terminal, the gate terminal, and the first power supply terminal, the base terminal is electrically connected to the second anode terminal and the second power supply terminal via the first resistance element, the emitter terminal is electrically connected to the gate terminal, the second cathode terminal, and the first anode terminal, and the collector terminal is electrically connected to the first power supply terminal. an electrostatic protection circuit; and a MOSFET including a gate terminal, wherein the electrostatic protection circuit includes a positive-side first power supply terminal, a negative-side second power supply terminal, a first protection diode including a first cathode terminal electrically connected to the first power supply terminal and a first anode terminal electrically connected to the gate terminal, a second protection diode including a second anode terminal electrically connected to the second power supply terminal via a first resistance element, and a second cathode terminal electrically connected to the gate terminal, and a bipolar transistor including a base terminal, an emitter terminal, and a collector terminal, a positive-side first power supply terminal, a negative-side second power supply terminal, a first protection diode including a first cathode terminal electrically connected to the first power supply terminal and a first anode terminal electrically connected to the gate terminal, a second protection diode including a second anode terminal electrically connected to the second power supply terminal via a first resistance element, and a second cathode terminal electrically connected to the gate terminal, and a bipolar transistor including a base terminal, an emitter terminal, and a collector terminal, wherein the first protection diode, the second protection diode, the bipolar transistor, and the first resistance element are respectively formed on a semiconductor substrate made of silicon carbide, the bipolar transistor is electrically connected to the second anode terminal, the gate terminal, and the first power supply terminal, the base terminal is electrically connected to the second anode terminal and the second power supply terminal via the first resistance element, the emitter terminal is electrically connected to the gate terminal, the second cathode terminal, and the first anode terminal, and the collector terminal is electrically connected to the first power supply terminal.