A method and device for supporting optical transmission network service dispatch in an optical synchronization network, said device comprises service cards (401, 407), backplane interface (404) and a plurality of dispatch units (405, 406), wherein, the service cards (401, 407) process the service signals and distribute them to the backplane structure frame according to the bandwith of the service signals, and connect with the corresponding dispatch units (405, 406) through the backplane structure frame, and then the dispatch units (405, 406) execute the service dispatch. Said dispatch units (405, 406) can work independently from each other, and the dispatch units can be added linearly according to the bandwidth of the signal. The present invention can compatibly implement the uniform dispatch of the ODU and SDH service on the basis of the existing optical synchronization device without changing the backplane frame structure or increasing the backplane speed.