By taking “26 ℃ air conditioning energy conservation motion” as the research background, this paper analyzed the comfort and energy-saving performance of temperature control air-conditioning system. Then, a comparison of the Predicted Mean Vote (PMV) values of two connected rooms in different orientations revealed that, at the same temperature, different average radiation temperatures caused different comfort indexes. The same temperature control standard usually resulted in uncomfortable environment. The energy-saving differences between the temperature and the comfort index control of air conditioning system in summer and winter were analyzed, which illustrated that the temperature control embodied neither heat comfort nor energy-consumption, and comfort index control, like PMV index control, is one of the effective methods which ensures comfort and considers the energy-saving requirement of air conditioning system.