This paper raises the concept of ”soft disciplinary constraint” to explain why the party-state of the Chinese Communist Party (CCP) faces difficulty to constrain the power of its leading cadres. This paper points out that reforms directed to ”separation of powers” need to be taken to overcome this problem. After examining four reform cases taken by Hu Jintao, this paper finds that although the CCP has also come to such an understanding, it still cannot fully implement such reforms, because to really have separation of powers would inevitably destroy some of its basic organizational principles such as ”democratic centralism,” ”collective leadership,” or ”party leadership over the state.” This paper argues that the ”soft disciplinary constraint” will thus become the most important internal constraint for CCP's democratic transition as a ”post-totalitarian authoritarian regime.”