A method and system for broadcasting a multimedia message are disclosed. The method includes: a broadcasting source node packs multimedia content to be broadcasted into a multimedia message, and sends the multimedia message to a reception end node in structural Peer-to-Peer which establishes a virtual connection with the present broadcasting source node; the reception end node receiving the multimedia message forwards the multimedia message to other reception end nodes establishing a virtual connection with the present reception end node. The method and system can save bandwidth and processing capability resources of the whole overlay network, and can make loads be distributed to nodes except the broadcasting source node more evenly to prevent the broadcasting source node from being bottleneck.