From the Asian Finance Crisis in 1997, to many scandals in U.S.A. in 2001, and lots of fraudulent practices for many years in Taiwan, these cases severely injured the investors and the whole society. In fact, before these fraud cases happening, a lot of scholars have proposed that manager can manipulate reports with accounting tactics to manage earnings and window dress the performance of the company. After these scandals bursting, the researches which discuss how to regulate CEO¡¦s behavior by using corporate governance mechanism get more attentions. A lot of researches point out that CEO¡¦s option-based compensation might be one of the reasons which result in the self-interested behavior, and provide their views about the monitoring effects of the corporate governance mechanism. However, the researches that discuss whether CEO¡¦s self-interested behavior will influence the monitoring effects of the corporate governance mechanism are few. This paper divides the pubic listed company that had issued warrants to CEO from 2001 to 2005 into two groups by the ratio of option-based compensation in CEO¡¦s total compensation. We want to know that whether the corporate governance mechanism has the same influence in earnings management and company¡¦s performance in different CEO¡¦s option-based compensation ratio. The corporate governance and compensation variables we used are institutional ownership in the firm, the number of institutional directors, board size, percent of independent outside directors on the board, percent of inside directors on the board, director and executive officer stock ownership, company size, and CEO¡¦s option-based compensation ratio. The conclusions as follows: 1. CEO¡¦s option-based compensation ratio forms the threshold effect to the monitoring effect of the corporate governance mechanism. When CEO¡¦s option-based compensation takes particular proportion of total CEO¡¦s compensation, the corporate governance mechanism will be more effective. 2. The corporate governance mechanism that has significant influence in earnings management and operating performance will be different when CEO¡¦s option-based compensation ratio is different. 3. Among these corporate governance mechanism, percent of independent outside directors on the board is the only one that can have similar and significant influence in earnings management no matter how high the CEO¡¦s option-based compensation ratio is. It may relate to the independence of independent outside directors.