Disclosed are a method and an apparatus for operating based on a power save mode in a wireless LAN. The method for operating based on the power save mode in a wireless LAN may comprise the steps of: an AP receiving, from a first STA, a first trigger frame for triggering the transmission of first downlink data which has been buffered for the first STA; the AP determining a temporary halt of the transmission the first downlink data, which is transmitted as a response to the first trigger frame, based on a first priority rank of the first downlink data which has been buffered for the first STA, a second priority rank of second downlink data which has been buffered for a second STA, and a point when the second STA is switched to an awake state; and the AP transmitting, to the first STA, a temporary halt setting frame for indicating the temporary halt.