Abstract: “The integration of party leadership into various aspects of corporate governance” is a key characteristic of corporate governance in state-owned enterprises. Empirical analysis of data from heavily polluting state-owned manufacturing enterprises reveals that in the process of pursuing green development in state-owned enterprises, Party leadership can effectively improve their green performance. The leadership of the Party has ultimately improved the overall green performance of enterprises through three mechanisms: increasing green investment, promoting green output, and enhancing green management. In addition, although the leadership of the Party can significantly promote corporate emissions reduction in promoting green output, its role in promoting green innovation is not significant. Further research has also found that the regulatory role of the Party’s leadership in the process of transforming green performance into overall corporate performance is currently not significant. The above results indicate that the leadership of the Party is an important guarantee in the green activities of enterprises. But it is necessary to study the ways and methods for the Party to play a governance role from the perspective of promoting innovation and improving business operations, in order to achieve high-quality transformation of enterprises.