The invention relates to a communication system and a carrier aggregation method of the wireless communication system, particularly relates to a novel wireless communication system and a carrier aggregation method thereof, and belongs to the technical field of electric power information. The system comprises a wireless base station module and a wireless terminal module. The wireless base station module and the wireless terminal module are connected to achieve carrier aggregation during data transmission. The wireless base station module is used for sending local frequency point switching signaling according to the data receiving quality, and the wireless terminal module is used for switching frequency points according to the local frequency point switching signaling sent by the wireless base station module during data transmission. By means of the system and the method, carrier band frequency spectrum continuity can be achieved, the system can achieve frequency band aggregation easily, the signaling cost and frequency points required to be detected by the user terminal are small, and the transmission equipment cost can be saved.