A method, a base station, and a system are provided for synchronizing an LTE-TDD network and a WiMAX network. The method includes: synchronizing the LTE-TDD network and the WiMAX network with a same clock source; determining a frame format of the WiMAX network; determining a half-frame format of the LTE-TDD network according to the frame format of the WiMAX network, and determining a delay time between a frame header of the half-frame format of the LTE-TDD network and a frame header of the frame format of the WiMAX network, so that the LTE-TDD network and the WiMAX network are synchronized.