Carbon dioxide heat pump water heater for recovering bath water afterheat

The invention discloses a carbon dioxide heat pump water heater for recovering bath water afterheat in the technical field of household appliances. An inlet of a carbon dioxide compressor is connected with an outlet of an evaporator; an inlet of a gas cooler is connected with the compressor; an outlet of a throttling mechanism is respectively connected with an outlet f the gas cooler and an inlet of the evaporator; an evaporator shell is positioned below a spray header; a filter unit is arranged between the evaporator and the spray header; an evaporator fan is arranged in the wall of the evaporator shell; one path of running water pipe is communicated with a cold and hot water flow controller; the other path of running water pipe is connected with a heating tank so as to exchange heat with the gas cooler and is connected to the cold and hot water flow controller through a heat pump circulating pipe; and after water is heated, the water flows through the heat pump circulating pipe, also flows through the cold and hot water flow controller, is adjusted to have proper temperature through the cold and hot water flow controller, and flows out from the spray header for the bath of residents. The temperature drop of used hot water is small, and the used hot water flows through the evaporater for recovering the afterheat, and then is discharged so as to save energy.