A Time Division Multiplex (TDM) data transmission method is based on the communication system sharing the transmission media, sets TDM logical ports on both transmitting side and receiving side, and establishes the corresponding relationship between the transmitting side logical port and the receiving side logical port; while transmitting TDM data, original TDM data is mapped to package data format by the set TDM logical port, then the resulting package data and Connection ID (CID) is directly encapsulated into Media Access Control (MAC) data package according to the set encapsulation information, and ultimately send to the receiving side through the common transmission channel; the receiving side obtains the stored decapsulation information and the corresponding receiving side TDM logical port ID information by its MAC layer according to the CID in the received data package, and then decapsulates the data package, and maps the resulting data onto the corresponding receiving side TDM logical port, thereby achieves the efficient transmission of TDM data.