In a wireless LAN environment, when downlink network load reaches a certain level, an access point (AP) cannot transfer its whole pending packets to stations (STAB) during one beacon transmission interval. This results in unnecessary power consumption of STAB in idle mode compared with that of STAB in sleep mode. Proposed scheme restricts the number of STAB to be marked in beacon when congestion occurs and its performance regarding power consumption is evaluated. The result shows the considerable normalized energy conservation of STAB as the traffic load is increasing.