To provide a hot water supply device recovering heat by preventing an adverse influence on high temperature hot water, and reheating a bathtub by utilizing a heat recovery heat exchanger.

This hot water supply device is provided with: a tank side circulating passage 17 for making the high temperature hot water flow out of an upper part of a heat storage tank 10 to flow in a lower part of the heat storage tank 10; a connecting flow passage 18 for making low temperature hot water flow out of the lower part of the heat storage tank 10 to flow in a midway part of the tank side circulating passage 17; a changeover valve 19 arranged on a connection point between the tank side circulating passage 17 and the connecting flow passage 18 and switching the tank side circulating passage 17 side and the connecting flow passage 18 side; a bathtub side circulating passage 33 for making bath water in a bathtub 30 flow out to an external part to flow again in the bathtub 30; and a heat exchanger 40 for exchanging heat between the high temperature hot water or the low temperature hot water flowing on the downstream side of the changeover valve 19 of the tank side circulating passage 17 and the bath water flowing in the bathtub side circulating passage 33.