Abstract: Objective Proposal of emergency rescue against possible hydrogen sulfide leakage accident in a sulfur recovery unit facility was studied. Methods The consequence of hydrogen sulfide leakage accident in a sulfur recovery facility was simulated with the application of simulation software,based on the production process,the raw and auxiliary materials,the major equipment,the information on occupational health and other related data. Then the corresponding emergency rescue measures were present. Results If hydrogen sulfide leakage occurred in the acidic gas separation tank,the isopleth of ERPG-3 or IDLH was located at about 60 m downwind, the isopleth of ERPG-2 at about 148 m downwind and that of the ERPG-1 located at about 5 980 m downwind. Conclusion The simulation of hydrogen sulfide leakage could clearly show the affected extent and scope of toxic clouds. It is useful to guide the occupational health emergency rescue.