Embodiments of the present invention provide a communications method and device for a single-frequency WLAN. An AP monitors a CTS or RTS packet whose receiver or sender is a neighboring AP inside the single-frequency WLAN; and when a CTS or RTS packet whose receiver or sender is a neighboring AP inside the single-frequency WLAN is detected, a channel in a coverage direction of the AP is cleared. Multiple APs in the single-frequency WLAN form one “omnidirectional group”. When any of the APs in the “omnidirectional group” performs RTS/CTS exchange with a STA inside a coverage area of the AP, neighboring APs can also work cooperatively, channels in coverage directions of the neighboring APs are cleared, and data communication in the coverage directions of the neighboring APs is suspended, thereby effectively avoiding network conflicts, and improving network performance of the single-frequency WLAN.