Gas meter, valve and reverse ventilation prevention assembly thereof

The utility model provides a gas meter, a valve and an anti-reverse ventilation assembly of the valve, the anti-reverse ventilation assembly is installed at a sealing opening of a valve seal of the valve, and the sealing opening of the valve seal is respectively communicated with a gas inlet of the valve and a gas outlet of the valve; when airflow flows from the air inlet to the air outlet, the reverse ventilation prevention assembly is in a conducting state, and the airflow circulates normally. When airflow flows from the air outlet to the air inlet, the reverse ventilation prevention assembly is in a cut-off state, and the airflow stops flowing. According to the gas meter, the valve and the reverse ventilation prevention assembly of the valve, the problem that in the prior art, a reverse ventilation prevention assembly interferes with a valve seal is at least solved. 本实用新型提供一种燃气表、阀门及其防反向通气组件，其中防反向通气组件安装在阀门的阀封封闭口，所述阀封封闭口分别与所述阀门的进气口和所述阀门的出气口相连通；气流从所述进气口流向所述出气口时，所述防反向通气组件处于导通状态，气流正常流通；气流从所述出气口流向所述进气口时，所述防反向通气组