Abstract: A pilot burner safety device of a gas combustion apparatus for shutting down a gas supply valve automatically at poor oxygen condition, includes an air intaking air means for intaking into a gas supplying passage, a heat detecting means mounted adjacent to the flame nozzle and an intaking control means mounted adjacent to the flame nozzle for controlling an air volume through the air intaking means by detecting flame temperature at the flame nozzle, and an air control means including a shape memory alloy which closes the halves of the air intaking means as a first step and opens the whole of the air intaking means at a heated condition, thereby avoiding nonignition phenomena at the initial ignition, and achieving a firing in one ignition operation.