Using the sample data of listed companies from 2009 to 2014,this paper not only studies the reason of over-investment in state-owned enterprises from internal and external aspects,but also studies how ultimate controller influences the overinvestment of state-owned enterprises. The results indicate that in the state-owned enterprises,over-investment still exists.Government intervention is the external factor which may lead to the over-investment of state-owned enterprises and managerial entrenchment is the ...