Communication method and communication apparatus for wireless lan system supporting multi bandwidth

Disclosed are a communication method and a communication device of a wireless LAN system supporting multiple bandwidths. A communication method of a wide-area wireless LAN system according to one embodiment of the present invention includes the following steps: a step wherein a communication device of a network supporting multiple bandwidths generates a base frame based on either a first bandwidth, which has the lowest signal-to-noise ratio among predetermined bandwidths, or a second bandwidth which is two times wider than the first bandwidth; a step wherein the communication device constructs a duplication mode frame based on the base frame; and a step wherein the communication device transmits the duplication mode frame through multiple bands.