A format that includes a BSSID of a transmitting station within a preamble of the frame is an HE format, and a format that does not include a BSSID within the preamble but includes a BSSID in a MAC header is a Non-HE format; and a wireless station in the BSS includes a control part which checks a format of a frame received at a predetermined receiver sensitivity or above, and continues demodulation of the received frame if the format is HE format and the BSSID in the received frame is consistent with its own BSS, and stops the demodulation of the received frame if the HE format and the BSSID in the received frame is not consistent with its own BSS.