This research discussed the influence between directors and supervisors and the separation of ownership and control toward enterprise value according to the convergence of interest hypothesis and the entrenchment of interest hypothesis. The result indicated that, from 2003 to 2008, directors and supervisors¡¦ shareholding ratio and chair ratio of Taiwanese listed information service corporations had a negative relation with enterprise value. The shareholding ratio of substantial shareholders had a positive relation with enterprise value ¡V the shareholding ratio of directors and supervisors had the convergence and the entrenchment of interest effect on enterprise value. The more cash-flow rights the control shareholders owned, the higher the enterprise value was. When we used specific percentage to discuss the nonlinear relation between equity transparency and enterprise value, we discovered that the nonlinear relation between Proxy Q and the separation of ownership and control did not exist. However, there existed a ¡§W-shaped¡¨ nonlinear relation when the dependent variable was ROA or ROE. It can explain that the implementation of corporate governance on enterprise value has a certain degree of influence. Nonetheless, whether the effect is good or bad depends on what role one plays in the enterprise.