Governance has various structures, and involves complex decision-making. In contrast to the Western governance systems, China has the dual Party-state governance system for managing different levels of governmental agencies. Under the design of such a system, the system of Chinese Communist Party Schools (CCPS) has specific missions and agendas to train all levels of governmental leaders in the process of policy formulations and implementations. This article utilizes the school principals' professional development program of Suzhi education in Shanghai in 2016, in which the CCPS and Shanghai Municipal Education Commission shared their power interdependence relationship, as a case. Through document analysis and semi-constructed interviews of different stakeholders, this article reports that in the implementation of Chinese education policy, the Chinese Communist Party (CCP) holds the leading power in providing policy directions for the CCPS professional development program, which aims to train educational leaders. Building a stable and interactive relationship between CCPS and the education system through professional development program is beneficial for maintaining the CCP's leading power and strengthening the CCP's influence in the process of education policy implementation.