Embodiments of the present invention disclose a method, an apparatus, and a system for selecting a network device. The method includes: receiving, by a second network device, a network device selection message sent by a first network device, where the network device selection message contains a VLAN mapping capability identifier of the first network device; and selecting, by the second network device, according to the VLAN mapping capability identifier and local VLAN mapping capability, a network device for executing VLAN mapping. By using the technical solutions provided in the embodiments of the present invention, execution of VLAN mapping for a bidirectional pseudo wire (PW) between two network devices on a same network device may be implemented, and there are only two VLAN identifiers on the bidirectional PW, thereby ensuring consistency of VLAN mapping and making it simpler and easier to maintain and detect the PW.