To further promote the three-year action of SOE reform，it is the key to improve the construction of the board of directors. The construction of full-time outside directors is an important grasp to implement the board of directors’ mandate and build an efficient board of directors. The establishment and promotion of full-time external directors is important to improve the structure of the board of directors and enhance the professional governance ability of directors. This article summarizes the “four-in-one” organizational model of full-time external director management developed during the three-year reform of state-owned enterprises，taking into account the management of full-time external directors already carried out by state-owned enterprises，and proposes the “four-in-one” organizational model under which China Huaneng Group，a central power enterprise，has implemented a comprehensive system of full-time external directors in terms of system construction，responsibility positioning，selection and appointment procedures，performance training，evaluation and incentive，and exit mechanism. Under this organizational model，China Huaneng Group has implemented a full range of practical exploration of the system structure，responsibility positioning，selection and appointment procedures，performance training，assessment and incentive，and exit mechanism，which provides a reference and useful reference for further promoting the management of full-time external directors in state-owned enterprises.