Abstract: A safety timing control device is provided for a gas appliance and includes an electromagnetic switch, a first timing controller, a second timing controller, a power converter, and an alarm unit. The electromagnetic switch includes an electromagnet, a return spring, a housing, a connection bar, and a plug. The first timing controller sets a predetermined period of operation of the gas appliance in order to control the supply of electrical power to the electromagnet, which in turn opens or closes a gas passage of the gas appliance to prevent a potential risk of explosion caused by undesired continuous supply of fuel to a flaming site of the gas passage or to prevent a potential risk of being poisoned by carbon monoxide generated by incomplete combustion of fuel gas in the gas appliance.