A method and device for synchronizing clock time transport modes in an optical transport network. The method comprises: when a clock time synchronization interruption alarm occurs in a clock time node, sending a currently used clock time transport mode to a receiving end, and the receiving end updating a clock time transport mode of a local current clock time node according to the received clock time transport mode; and receiving a clock time transport mode response fed back by the receiving end, and completing synchronization with the clock time transport mode of the receiving end. By synchronizing clock time transport modes of a receiving end and a sending end, the embodiments of the present invention realize correct transmission of clock time signals of the two ends, thereby improving the efficiency and stability of signal transmission.
