The core of internal corporate governance is to properly configure the management power to facilitate a variety of institutions and policies to promote the companys operational efficiency. In this paper, we analyze the relationship of internal control effectiveness and overinvestment. Further, we discuss the effect of management power on the internal control effectiveness and overinvestment. We found that：1）the more effective the internal control is, the lower level overinvestment will be; 2) For Chinas listed SOEs, the management power will a weakening negative effect on internal control effectiveness on the level of overinvestment. On the condition that the management power is more centered, the effect of internal control over the overinvestment will not be apparent.