PROBLEM TO BE SOLVED: To provide a hot water supply device capable of suppressing no-water burning of a heating unit due to erroneous detection of a water flow detection unit.SOLUTION: A hot water supply device 1 includes: a heating unit 10 for heating water; a water flow detection unit 20 for detecting the presence/absence of water flow flowing into the heating unit 10; a discharge function unit 40 for discharging water heated by the heating unit 10; and a heating control unit 51 for controlling a heating amount of the heating unit 10. In the hot water supply device, in a period from the time when water starts circulating to the heating unit 10 firstly to the time when a predetermined time is elapsed, detection of the presence/absence of water flow with the water flow detection unit 20 is invalidated, and the heating control unit 51 stops heating operation of the heating unit 10.
