To provide an electric water heater that achieves the reduction of a power consumption (utility costs) by effectively using the power of a solar battery panel to raise the temperature of water.

The electric water heater includes: a water storage tank 20 that stores water internally; a water supply section 22 that supplies the water into the water storage tank 20; a hot-water supply part 24 that is arranged in an upper part of the water storage tank 20 and sends the water to the outside of the water storage tank 20; a main heating part 26 that is driven by an AC voltage supplied from a commercial power supply, and heats the water in the water storage tank 20; the solar battery panel 10; an auxiliary heating part 28 that is driven by a DC voltage supplied from the solar battery panel 10, and heats the water in the water storage tank 20; and a water heater control device 40 that controls the drive of the main heating part 26 and the auxiliary heating part 28.