To provide a hot water storage heating apparatus capable of lowering a temperature of hot water flowing in a hot water circulation circuit without requiring a dedicated water discharge passage and water discharge on-off valve.

A hot water storage heating apparatus 1 includes: a hot water storage tank 41; an external heat source 2 for heating hot water in the hot water storage tank 41; a hot water circulation circuit 45 circulating hot water between the external heat source 2 and the hot water storage tank 41; and a hot water heating circuit 48 having an expansion tank 80 capable of storing heating water heated via heat storage in the hot water storage tank 41. The hot water storage heating apparatus 1 includes: a replenishing passage 95 having a lower end connected to the expansion tank 80 to supply the heating water to the expansion tank 80; an on-off valve 96 installed in the replenishing passage 95; and a control means 97 switching an opening/closing state of the on-off valve 95. An upper end of the replenishing passage 95 is branched and connected to a return side passage of the hot water circulation circuit 45, and hot water flowing in the hot water circulation passage 45 can be supplied to the expansion tank 80 via the replenishing passage 95.