With the development of China's economy, people's demand for energy is increasing. However, in order to improve the efficiency of energy use and protect the human environment, it is necessary to increase the energy-saving reform of cogeneration system. Starting from the relevant theoretical analysis of cogeneration system, this paper expounds the main contents of energy-saving reform of cogeneration system, and proposes that the future reform of cogeneration system should focus on increasing theoretical research, so as to achieve the goal of further energy saving.