Disclosed are a multicast data forwarding method and device supporting a virtual terminal. The method includes: a bridge forwarding module receiving multicast data sent by an end station and determining output ports; when a certain output port is the same with the input port of the multicast data and the input port has enabled reflective relay function, not carrying Ingress extended channel identifier (Ingress_E-CID) in the forwarded message information or the value of the Ingress_E-CID being zero. By modifying the source port filtering mechanism, the present invention enables a Port Extender (PE) supporting the virtual terminal technology to transmit and receive data normally while multicasting.