A service processing path allocation method for allocating an executed service processing path to a service flow, comprising: receiving, by a router, a service packet of a user, and obtaining a user identifier and Internet Protocol, IP, 5-tuple information according to the service packet, wherein the IP 5-tuple information comprises information about a source IP address, a destination IP address, a source port, a destination port, and a communications protocol; characterised by querying, by the router, a service processing path table for a target service processing path corresponding to the user identifier and the 5-tuple information, wherein the target service processing path comprises information about at least one service execution entity, and each service execution entity is configured to perform one type of service processing on the service packet, wherein the service processing path table comprises a level-1 service processing path table and a level-2 service processing path table, wherein the level-1 service processing path table comprises a plurality of first service processing paths and the level-2 service processing path table comprises a plurality of second service processing paths, wherein the first service processing paths comprise the user identifier, the 5-tuple information, information about a service execution entity configured to perform layer L4 processing on the service packet, and an identifier indicating whether to perform layer L7 processing; and wherein the second service processing paths comprise the user identifier, the 5-tuple information and information about a service execution entity configured to perform layer L7 processing on the service packet; and sending, by the router according to the target service processing path after encapsulation is performed on the service packet, an encapsulated service packet to a first-hop service execution entity in the target service processing path for corresponding service processing, wherein the encapsulated service packet comprises the user identifier. receiving, by a router, a service packet of a user, and obtaining a user identifier and Internet Protocol, IP, 5-tuple information according to the service packet, wherein the IP 5-tuple information comprises information about a source IP address, a destination IP address, a source port, a destination port, and a communications protocol; characterised by querying, by the router, a service processing path table for a target service processing path corresponding to the user identifier and the 5-tuple information, wherein the target service processing path comprises information about at least one service execution entity, and each service execution entity is configured to perform one type of service processing on the service packet, wherein the service processing path table comprises a level-1 service processing path table and a level-2 service processing path table, wherein the level-1 service processing path table comprises a plurality of first service processing paths and the level-2 service processing path table comprises a plurality of second service processing paths, wherein the first service processing paths comprise the user identifier, the 5-tuple information, information about a service execution entity configured to perform layer L4 processing on the service packet, and an identifier indicating whether to perform layer L7 processing; and wherein the second service processing paths comprise the user identifier, the 5-tuple information and information about a service execution entity configured to perform layer L7 processing on the service packet; and sending, by the router according to the target service processing path after encapsulation is performed on the service packet, an encapsulated service packet to a first-hop service execution entity in the target service processing path for corresponding service processing, wherein the encapsulated service packet comprises the user identifier.