To provide a heat pump water heater capable of obtaining a tapping temperature of 60C or higher even in winter when a tap water temperature is low.

Independent refrigerant cycles with two compressors and two circuits are used and separated for low temperature stage heating and high temperature stage heating. In winter, the refrigerant cycles are combined to attain tapping by heating tap water of 5C to about 35C in the refrigerant cycle for low temperature stage heating and then to 65C in the refrigerant cycle for high temperature stage heating. A double tube type heat exchanger is used as a condenser, i.e., a heater for hot water supply, and a tapping temperature higher than a condensation temperature can be obtained making most of the sensible heat of superheated refrigerant gas of high temperature discharged from the compressor.