Disclosed are a link adaptation method and device in an active scanning method. The link adaptation method transmits a the probe request frame comprising null data packet announcement (NDPA) information elements, transmits a null data packet (NDP) frame comprising only a physical layer convergence protocol (PLCP) header after transmitting the probe request frame, and receives a the probe response frame comprising feedback information elements measured based on the NDP frame. Therefore, the invention is capable of improving data transmission efficiency by using a modulation coding scheme (MCS) suitable for a channel state from initial connection.