Disclosed are a method for measuring a cell in a wireless access system and a device therefor. Specifically, the method comprises the steps of: receiving a pattern for reference signal received power (RSRP)/reference signal received quality (RSRQ) measurement; measuring a received signal strength indicator (RSSI) from a plurality of subframes included in the pattern for the RSRP/RSRQ measurement; extracting almost blank subframes (ABSs) from the plurality of subframes included in the pattern for the RSRP/RSRQ measurement by using the measured RSSI; and measuring the RSRP/RSRQ from the plurality of subframes included in the pattern for the RSRP/RSRQ measurement in consideration of the extracted ABSs.