A reference voltage generation circuit has transistors generating a PTAT current that increases in proportion to temperature, a transistor generating a CTAT current that decreases in proportion to temperature, a first variable resistor adjusting an output voltage, a transistor supplying the PTAT current to the first variable resistor via a first switch, a transistor supplying the CTAT current to the first variable resistor via a second switch, and a second variable resistor adjusting the CTAT current. The first switch is on in first and third operation modes and off in a second operation mode. The second switch is on in the first and second operation modes and off in the third operation mode. Switching the operation modes realizes independently outputting a PTAT voltage or a CTAT voltage. Independently adjusting the voltages makes it possible to correct output reference voltage of the reference voltage generation circuit accurately at low cost.