The objective existence of information asymmetry and accounting uncertainty requires a rational enterprise to manage earnings. The earnings management is neutral and different from the profit manipulation. It can moderately make up the rigidity and incompleteness of contracts, and help to enhance the information of earnings and guide resource allocation prospectively. But the earnings management is still a type of accounting information distortion. Improving the stock market regulation can help to reduce the policy incentives of earnings management；strengthening the accounting principles and accounting system development can narrow the management of the space; improving corporate governance structure and raising certified public accountants occupational level can sound the administration of internal and external binding mechanism.