The utility model relates to an automatic gas inlet and discharge valve, which comprises a valve cover and a valve body. The valve cover is arranged on the valve body. The automatic gas inlet and discharge valve is characterized in that a valve core is arranged in the valve body. A float is arranged in the valve core. The top end of the valve cover is provided with an exhaust hole. The lower end of the valve body is provided with a pipeline interface for assembly. The automatic gas inlet and discharge valve has the technical advantages that the automatic gas inlet and discharge valve simultaneously has the function of integrally gas inlet and discharge, a gas inlet and discharge process is fully and automatically carried out, and labor management is not needed; the lower end of the automatic gas inlet and discharge valve is provided with a thread pipeline interface of a standard pipe, the automatic gas inlet and discharge valve can be directly installed on the upmost end of a pipeline, and the automatic gas inlet and discharge valve is convenient to operate; the automatic gas inlet and discharge valve has small volume, light weight, good anticorrosion performance, and convenient and reliable use; the automatic gas inlet and discharge valve has wide application range and favorable commerce development prospect.