This paper proposes a system for energy conservation to be connected to a network. The system consists of a global controller and several room-mounted distributed controllers. Each room-mounted distributed controller’s roll is to collect environmental information such as temperature and humidity and to transmit the information to the global controller. The global controller’s roll is to determine the preset temperatures of the air conditioner to be achieved between the energy conservation and the amenity. The proposed approach is applied to model system, and the results show that the system is able to improve energy conservation.