The origin of earnings management is moral hazard from information asymmetry, which will disturb the efficiency of the capital market. Based on this, this paper choses social responsibility(CSR) as perspective to analyze the effect of CSR on earnings management. It is found that CSR can constrain the behavior of earnings management for corporations, and reduce the total level of earnings management. Moreover, considering the patterns of earnings management, CSR mainly controls the real activities earnings management. And when the corporations have stronger motivations, the effect of CSR on earnings management will not change.