Electric vehicle (EV) charging & swapping station is an indispensable EV energy service infrastructure after the large-scale industrialization of EV. Power line carrier communication (PLC) is a technology that transmits analog or digital signal with high speed through the carrier. By applying robust and reliable power line as the transmission medium of carrier signal, PLC is featured with stable and reliable information transmission, reasonable routing, no re-wiring, wide coverage, convenient connection, and highly reliable channel. This paper briefly describes the characteristics and applications of PLC technology, introduces functions and an overall design plan for the communication network of EV charging and swapping stations. Meanwhile, it provides the hardware realization and protocol establishment of communications network interfaces for PLC-based EV charging and swapping stations as well as a design for information management system.