The utility model relates to an area is from cleaning system's ammonia escape sampling device, in particular to to an ammonia escape sampling device, include sampling gun I, strain dust hood I, air blowing pump I, control flap I, sampling gun II, strain dust hood II, air blowing pump II, control flap II, aspirator pump, sensor and singlechip, the utility model provides an ammonia sample dress paper of escaping can clean the sampling gun by oneself and prevent that the sampling gun from blockking up the result that causes sampling test and the deviation appearing, and process line that simultaneously can the two sampling guns of reasonable distribution avoids the machine excess load to use, prolongs device lifetime, the resource of having practiced thrift a large amount of manpower and material resources.