To provide a water supply apparatus capable of discharging water in the vicinity of a bottom face of a tank without providing a recess in the bottom face of the tank and reduce size of the tank.

The water supply apparatus comprises a tank 112 for storing water therein, a water supply pump 114 comprising an impeller 118 extending from the vicinity of the bottom face in the tank 112 toward a tank cover 113 and a tubular case 119 covering the impeller 118, a driving section 115 disposed outside of the tank cover 113 for driving the impeller 118, and a tubular discharge pipe 116 extending from a side face of the case 119 of the pump 14 to the outside of the tank 112. Water in the vicinity of the bottom face of the tank 112 is discharged out of the tank 112 by rotating the impeller 118 by the driving section 115.