To prevent problems causing liquid leakage from a battery for an auxiliary power source, and bad influence on service life of the battery even when the auxiliary power source is left in a state of being connected by mistake even after power failure recovery.

In this gas cooking stove for heating cooking which is operated by commercial power source 45 in non-power failure, and operated by the battery-type auxiliary power source 3 detachably connected to a connector 25 disposed on a cooking stove body in power failure, a normally closed output contact 61 of a relay 6 opened when the power is supplied from the commercial power source 45 is connected to the connector 25, and the power supply to the gas cooking stove from the auxiliary power source 3 connected to the connector 25 is cut off by opening the normally closed output contact 61.