The present invention relates to monitoring method and device by a terminal in a wireless communication system supporting carrier aggregation. Particularly, a monitoring method comprises the steps of: receiving indication of a first resource interval which is being cross-carrier scheduled by means of a first cell with respect to the first cell, comprising consecutive radio resources, and a second cell comprising non-consecutive radio resources; and, on the first resource interval, blind decoding control information, for a physical downlink shared channel (PDSCH) of the second cell, in a physical downlink control channel (PDCCH) of the first cell.