A packet processing method includes: receiving, by a traffic classifier, a first packet; determining, by the traffic classifier, in policy information in the traffic classifier and according to a first filtering rule that matches the first packet, a first service identifier that matches the first filtering rule, and an address, which matches the first filtering rule, of a first service routing trigger, where the policy information includes: a filtering rule, an address of a service routing trigger, and a service identifier corresponding to the filtering rule, where the filtering rule is used to identify a packet, and the service identifier is used to represent a sequence of a service node that processes the packet; and sending, by the traffic classifier, a second packet to the first service routing trigger, where the second packet is formed by adding the first service identifier to the first packet.