The invention discloses a method and device for achieving tangent ring user data message intercommunication. In an RRPP ring, a first transmission node receives a second Hello message sent by a first main node, the second Hello message carries a first encapsulated VLAN ID, and the first encapsulated VLAN ID is any VLAN ID in first RRPP embodiments except the VLAN IDs controlled by transmission node public devices. A first transmission node starts a PBB function in an RRPP domain, and the first encapsulated VLAN ID in the Hello message is saved. A non-RRPP port of the first transmission node receives a data message sent by a user, a user VLAN ID of the data message is a control VLAN of a first RRPP ring, the first transmission node inquires a mapping table corresponding to a target MAC of the data message, conducts PBB encapsulation on the data message, and forwards the data message, wherein the target MAC in an encapsulated BMAC is an inquired bridge MAC in the corresponding mapping table, a source MAC is the bridge MAC of the first transmission node, a BVLAN is a first encapsulated VLAN ID, and an I-SID is a preset value. According to the technical scheme, the method and device for achieving the tangent ring user data message intercommunication can achieve intercommunication of the data message with the control VLAN between users.