The utility model relates to a gaseous tail gas recovery device that detects of SF6 equipment, including negative pressure steel bottle and check valve, the opening coaxial sealing installation check valve of negative pressure steel bottle, setting pressure table and gas vent on this negative pressure steel bottle. The utility model discloses simple structure, design scientific and reasonable, think about ingenious easy operation, convenient to carry, safe firm, the hidden danger that has been punctured when having avoided with the gas collection bag prevents the harm that waste gas directness atmospheric dilution caused, is favorable to the environmental protection.