To provide a human body detecting device which facilitates the fitting of itself and can speedily and securely be operated.

This human body detecting device comprises hot-water equipment as a heat source device such as a bathroom heater, a remote controller for remotely operating and controlling the hot-water equipment, a controller which controls the hot-water equipment, a transmitter receiver provided to the hot-water equipment, a human body detection sensor which is provided in a bathroom to pick up an image of the movement of a human body and performs image processing, a transmitter which sends the signal from the human body detection sensor, and an annunciating means which is provided on the remote controller and gives an alarm through the abnormality detection of the human body detection sensor; when the human body detection sensor detects abnormality, its abnormality detection signal is transmitted from the transmitter to the transmitter receiver.