The application provides a message transmission method and a message transmission device. The method comprises the following steps: after receiving a first message, determining VPN (Virtual Private Network) information corresponding to the first message, and querying a forwarding table corresponding to the VPN information according to the destination IP address of the first message to get an outbound interface corresponding to the destination IP address; if the outbound interface is a GRE (Generic Routing Encapsulation) tunnel, packaging a first GRE tunnel header corresponding to the GRE tunnel for the first message to get a first GRE tunnel message, wherein the first GRE tunnel header contains the VPN information; acquiring an IPsec (IP Security) tunnel corresponding to the GRE tunnel, and packaging a first IPsec tunnel header corresponding to the IPsec tunnel for the first GRE tunnel message to get a first IPsec tunnel message; and sending the first IPsec tunnel message through the IPsec tunnel so that opposite-end equipment receiving the first IPsec tunnel message can send the first message according to the VPN information. Through the technical scheme of the application, the resources of the IPsec tunnel can be saved, and the public network address resources can be saved.