The invention provides a high-pressure gas safety valve. The high-pressure gas safety valve comprises a valve element, a steel ball and springs. The valve element is installed in a safety valve shell and is provided with a valve element channel connected with a high-pressure gas system. Gas pressure is conveyed to an outlet of the valve element through the valve element channel. The outlet of the valve element is provided with a conical face made of non-metal materials. The steel ball is arranged at the first end of a supporting base and can be matched with the conical face. The springs are arranged between the supporting base and a spring supporting base fixedly connected to the safety valve shell. Provided spring force is lower than set pressure so that the steel ball can be matched with the conical face to achieve sealing. According to the high-pressure gas safety valve, sealing is achieved through cooperation of the non-metal conical face of the valve element and the steel ball, and a good sealing effect is achieved.