A method for a power save mode operation in a wireless local area network (WLAN) system is provided. The method includes transmitting, by an access point (AP), a traffic indication map (TIM) element that announces existence of buffered traffic, wherein the TIM element includes an association ID (AID) assigned to a buffered STA having the buffered traffic when the buffered station (STA) is associated with the AP; receiving, by the AP, a poll frame for requesting data frame transmission from a candidate STA, wherein the poll frame contains an AID of the candidate STA and a medium access control (MAC) address which is a unique identifying information of the candidate STA; and determining, by the AP, whether the candidate STA is the buffered STA on the basis of the AID and the MAC address of the candidate STA.