A label management method, a data stream processing method, and a device, where the label management method includes allocating, by a controller, a source label to a data stream, sending, by the controller, a first Border Gateway Protocol (BGP) update packet to an ingress network device on a label switching path (LSP) of the data stream, and sending a second BGP update packet to an egress network device on the LSP of the data stream, where the first BGP update packet includes a stream identifier of the data stream and the source label, and the second BGP update packet includes a mapping relationship between the source label and a source object of the data stream. Hence, configuration, management, and maintenance can be simplified.