A gas control valve including a body having a throat formed in a bore, a post slidably received in the bore and including a plug, a pin laterally engaged on an upper portion of the post, and a spring for biasing the post so that the plug can be separated from the throat and so that gas may flow through the throat, and a guide fixed in top of the bore and having two inclined surfaces, the ends of the pin are slidable along the inclined surfaces, the plug can engage with the throat when the knob is pushed toward the body so that gas is prevented from flowing through the throat.