Abstract: On the basis of the simulation system coupling the region climate model RegCM2 with the atmospheric chemistry model,the distribution of anthropogenic sulfate aerosol over China area and its radiative climate responses have been studied and compared with the results of the holospheric model.The details methods for the climate responses of the radiative forcing of sulfate aerosol have been compared.The results show:① The coupling simulation system obtains more accurate results of the distribution law of sulfate and radiative responses than the atmospheric circulation model.② It has been clarified that there is difference in most region between results of the on-line and off-line methods both in sulfate burden and in radiative forcing having feedback or not at top of atmosphere(TOA) and in surface temperature response.The difference on regional average results is more obvious than that of large scale average results which is clear and cannot be neglected.③ By the further analysis to the climate responses,the simulation results show the gradually increasing uncertainties from sulfate contents to radiative forcing and surface temperature response.