Combining external financing and internal corporate governance, this paper discusses the corporate governance effect of convertible debt based on private benefits of control. This paper measures private benefits of control indirectly through managerial perks, overinvestment, free cash flow and dividends by cash, and then examines the difference of private benefits of control under different financial styles. The empirical results show that, managerial perks and firm’s free cash flow will decrease, and the dividends by cash will increase with the issuing of convertible debt; but we can not find the relationship between overinvestment and issuing of convertible debt. This research will be of some help to improve corporate governance and financial construct of Chinese enterprise, and will also bring some advice to advancement of Chinese financial innovation.