Disclosed is a subscriber loop carrier system wherein, to synchronize the phases of frames and multiframes from a plurality of subscriber loop carriers, corrections are made on the phases of frames and multiframes without relying on memory storage. The phase difference of the frame and multiframe phases with respect to a reference phase is detected at the receiving end. The detected phase difference is transmitted from the receiving end to the transmitting end. At the transmitting end, the phases of frames and multiframes being formed are controlled on the basis of the detected phase difference.