A method of negotiating channel sharing between adjacent cells when there are a plurality of cells in a power line communication (PLC) network. The method includes attempting to negotiate the channel sharing during a minimum contention access period (CAP) which starts after a maximum beacon period ends and ends before a CAP of each PLC cell ends, wherein the maximum beacon period indicates a maximum size that a beacon frame in a super-frame transmitted from a coordinator of each PLC cell can have. When an attempt to negotiate the channel sharing is made using this method, interference does not occur during channel sharing negotiation, and effective channel sharing can be achieved, thereby eliminating interference between adjacent cells.