The utility model provides a novel contain diagnosis of sulphur natural gas well mouth device, including separator, pressure transmitter, manometer and vice separator, the separator upper end still is connected with and the manometer through pipeline intercommunication, separator upper end with vice separator upper end, and vice separator upper end still is connected with pressure transmitter, and vice separator lower extreme is connected with the buffer tank, end entrance and separator lower extreme exit linkage on the buffer tank. This device compact structure, area is little, and measuring accuracy is high, and the working parameter wide range can must carry out online real -time measuring fast accurate to has light in weight, advantages such as roping convenience. This equipment still is equipped with hydrogen sulfide gas body detection instrument in addition, in case detect the hydrogen sulfide gas body, the instrument just can send the alarm to hydrogen sulfide content is shown on the detection instrument display, staff's safety can be effectively guaranteed. This equipment is applicable to the online real -time high accuracy measurement of producing gas, water production including sulphur natural gas well.