In the process of online monitoring of H2S gas concentration,due to its strong adhesion,it is easy to occur pipeline adsorption,resulting in deviations in measurement results,especially in the process of trace H2S detection.Therefore,it is particularly necessary to study the surface adsorption characteristics of H2S gas pipeline materials.In this work,a set of online H2S concentration measurement system is designed and constructed based on tunable diode laser absorption spectroscopy(TDLAS),and the measurement performance of the system is tested.On this basis,the adsorption characteristics of H2S on the surface of stainless steel materials at room temperature are investigated.The experimental results show that the online H2S concentration determination system has the characteristics of strong stability,low detection limit and high sensitivity,and can be used to achieve on line continuous determination of trace H2S concentration.After a series of experiments,it is proved that H2S has obvious and stable adsorption effect on the surface of stainless steel material,and the adsorption capacity per unit area of H2S on the surface of stainless steel material is 10 14(PCS /cm2).The experimental results can provide a certain reference for on line accurate measurement of trace hydrogen sulfide.