PURPOSE: To provide a combustion control device for the user's safe hot water supply heater which is protected from suspending combustion resultant from a temporary wrong operation, and prevented from supplying extraordinarily high temperature hot water even in an emergency.

CONSTITUTION: This combustion control device 1 comprises a combustion control means 3 which controls combustion based on setting temperature TS and detection temperature TH from a temperature detection means and a detection means 4 which outputs a first detection signal S1 when the detection temperature TH drops to a minimum level value and below, and outputs a second detection signal S2 when the detection temperature TH exceeds a maximum level value and an emergency detection means 5 which detects an emergency when the first or the second detection signal continues for a specified time.