The embodiment of the invention relates to the field of computer networks and discloses a multicast message processing method and a multicast message processing device. The method comprises the following steps of: receiving a multicast message, and acquiring a local router interface corresponding to the multicast message according to multicast routing entries carried by the multicast message; andmaking the multicast message pass through the acquired local router interface, and forwarding the multicast message to a cluster routing system for transmission. A plurality of pieces of routing equipment can be clustered into a virtual routing system which is a single routing node supporting multicast service externally, so that high-efficiency and reliable routing forwarding of the multicast message can be realized in a virtually polymerized cluster routing system. Therefore, the cluster routing system can efficiently support the multicast service at high quality.