Abstract: The deactivation kinetics equations of ethylene oxide synthesis silver catalyst were obtained from the calculation of real industrial data.The equations could represent the characteristics of catalyst deactivation. On the basis of the deactivation model, the boiling water temperature-time policy of ethylene oxide synthesis reactor was optimized.The optimal curve of boiling water temperature was obtained.It could enhance the economic benefits of ethylene oxide synthesis.Feasible approaches to optimizing reactor temperature of the same series of new catalysts were recommended.