Cleaner production is an efficient way to reduce the consumption of energy and environment pollution for electric power industry. But how to evaluate the performance of cleaner production is an inportant problem. In this paper, the performance evaluation index system of thermal power plants cleaner production is set up. Then we propose the intuitionistic fuzzy set group decision making methods to evaluate the performance of cleaner production of thermal power plants. At last we use an example to illustrate the efficiency of the methods.