Method and device for transmitting time division multiplexing (TDM) service

The invention provides a method and a device for transmitting a time division multiplex (TDM) service. The method comprises the following steps of: encapsulating a predetermined TDM frame signal of a first TDM network side into a grouped data packet; and transmitting the grouped data packet to a packet switching network. Due to the adoption of the method and the device, certain channels and certain time slots in the TDM frame signal can be selectively loaded to a data packet so that the bandwidth utilization ratio of the network can be increased.