The hydrogen has strong reflection sensitivity,and hydrogen observation is a new way to explore the forecast of earthquake. The on-line automatic trace hydrogen analyzer ATG-6118H is a new digital observation instrument used to measuring escaped hydrogen gas from the underground fluid,it can be fully automatic analysis of related samples on site,with the characteristic of high sensitivity,high degree of automation,low consumed,easy to operate,etc,and it has the function of network remote diagnosis and data processing analysis,and it can also accurately analyzes the trace hydrogen background value of air and well water. At present,there is no uniform testing standard of trace hydrogen analyzer in China,according to the actual testing requirements,calibration experiment,detection limit test,precision and accuracy experiments of the on-line automatic trace hydrogen analyzer ATG-6118H were carried out in this paper,and the performance of eight instruments was also compared. The feasibility of the instrument's performance detection method is determined by the index evaluation,so it is suitable for broad popularization and application of seismic subsurface fluid stationsas well as fault gas observation stations throughout the country with digital observation conditions.