Embodiments of this application relate to the communication field, and disclose a method, a device, and a system for transmitting a node identifier, to reduce a limitation on delivery of an SR POLICY route and improve network performance The method includes: A forwarding device sends a node identifier to a controller. The forwarding device receives a first SR POLICY route from the controller, where a target attribute of the first SR POLICY route is the node identifier. The forwarding device determines that the node identifier matches the target attribute of the first SR POLICY route, and forwards a traffic packet according to the first SR POLICY route.