WLAN channel resource distributing method and device and wireless local area network communication system

The invention provides a WLAN channel resource distributing method and device and a wireless local area network communication system. The method comprises the steps of acquiring subcarrier distributing information and sending data from subcarriers according to the subcarrier distributing information. The subcarrier distributing information is used for identifying the subcarriers which are used for carrying data, and the channel quality of the component channels which the subcarriers are arranged is larger than or equal to a judgment threshold. The WLAN channel resource distributing method reduces waste of terminal emitting power. Due to the fact that the terminal emitting power cannot be reduced by component channels with poor channel quality, modulation orders can be improved.