Downlink data receiving acknowledgement method and device

The present invention relates to the field of wireless communication technologies. Provided in embodiments of the present invention are a downlink data receiving acknowledgement (ACK) method and device for reducing system resource occupancy and improving a system throughput rate. The method comprises: receiving, by a station (STA), a signaling transmitted by an access point (AP), wherein the signaling of the AP is transmitted to m STAs, and the m STAs comprise the STA; if data of the AP transmitted to the STA is not aggregated data, then obtaining, by the STA and according to the signaling, an orthogonal sequence corresponding to the STA; and if the STA correctly receives the data of the AP transmitting to the STA, then generating, by the STA and according to the orthogonal sequence, a corresponding ACK frame, and transmitting, by the STA and at a first timeslot, the ACK frame to the AP.