Embodiments of the present invention disclose a packet processing method, including: obtaining, by a first network node, a format of a segment identifier of a second network node, where the format is used to describe a location and a length of each field in the segment identifier of the second network node, and the segment identifier of the second network node includes a first field; determining, by the first network node, a value of the first field in the segment identifier of the second network node based on a segment routing policy and the format of the segment identifier of the second network node, and adding the determined value of the first field to a second packet sent to the second network node, where the determined value of the first field is used to indicate the second network node to process the second packet. In the embodiments of the present invention, a prior-art problem that a programming capability of a network node is affected because an obtained format of a segment identifier of the network node cannot be displayed can be resolved.