Embodiments of the present invention provide a traffic bearer mapping method and a communication device. The traffic bearer mapping method includes: obtaining attribute information of a traffic data flow of a user; selecting a relay transmission tunnel according to the attribute information of the traffic data flow of the user; and mapping the received traffic data flow to the relay transmission tunnel for transmission, where the relay transmission tunnel includes a relay link radio bearer Un RB or a bearer including the Un RB. According to the embodiments of the present invention, transmission of a traffic data flow in an LTE-A network after a relay node is introduced into is implemented, thereby ensuring quality of service of multi-service.