Abstract: Tianjin seismic waves were inputted to a inhomogeneous rocky slope model, and the slope was analyzed by time-history method using general-purpose software ANSYS.In the POST1, dynamic safety factor distribution chart was calculated through programming, and then the dynamic safety factor was obtained.Based on reliability theory, the authors proposed the concept of reliability dynamic safety coefficient, and calculation method of the stability evaluation index of rock slope dynamic safety coefficient under the action of strong earthquake was given.Besides, the dynamic safety coefficient on dynamic safety coefficient distribution chart was identified.Resultsshowed that the dynamic safety coefficient slope reliability can be reliable under the consideration of project risk.