Water tank and heat pump water heater provided with same

The invention relates to a water tank and a heat pump water heater provided with the same. Specifically, the water tank provided by the invention comprises a tank body and a water inlet pipe. The tank body is provided with a bottom wall and a circumferential wall formed by stretching upward from the circumference of the bottom wall. The inner surface of the bottom wall protrudes upwards to form a rib or is recessed downwards to form a groove, so that a sewage discharge channel with the outlet end being located in the lowest position of the inner surface of the bottom wall is defined. The water inlet pipe is configured to be capable of conveying water to the inlet end of the sewage discharge channel, so that the flow direction of at least part of water is changed by the sewage discharge channel, and at least dirt in the zone, covered by the sewage discharge channel, of the inner surface of the bottom wall is taken to the lowest position of the inner surface of the bottom wall. In addition, the invention further provides the heat pump water heater provided with the water tank. According to the water tank, flow disturbance during sewage discharge can be improved, so that the bottom dirt of the water tank is removed more easily, and the sewage discharge effect is improved.