The invention provides a resource sharing method among virtual local area networks (vlans) in a power communication network. The method includes the following steps of building a vlan 1; adding a sharing port and independent ports into the vlan 1; building a vlan for each independent port; adding the sharing port and one independent port into a vlan corresponding to the independent port. By means of the method, resource sharing among different VLANs can be achieved, safety separation among different VLAN devices is not affected, network flooding of unknown groups of broadcasting messages in the power communication network can be prevented effectively, and network reliability is improved. A tagged or untagged mode output by the ports can be selected flexibly so as to adapt to the diversity of output messages of the device. For the cascading switch, VLAN sharing among far-end devices can be finished only through simple configuration of cascading ports.