In the present study, the mechanism of hydrogen sulfide decomposition on the Ni surface was investigated by kinetic Monte Carlo simulation. In this research the kinetic Monte Carlo simulation results agree qualitatively with the existing experimental data. The kinetics parameters for each step of suggested mechanism have been confirmed by simulation. By using the obtained mechanism and kinetics data, the system was studied at different temperatures and a comparison between kinetic data at different temperatures was provided. The effects of temperatures, hydrogen concentration and percent of hydrogen sulfide to catalyst on the rate of reaction were studied. Results demonstrate that temperature and ratio of H2S to catalyst are important parameters in the rate of reaction, while hydrogen concentration is not an effective parameter. (C) 2015 Elsevier B.V. All rights reserved.