Disclosed in the present application is a method for detecting a downlink control channel by a terminal in DRX mode in a wireless communication system applying carrier aggregation technique. Specifically, the method comprises the steps of: setting downlink control channel detection sub-frames in a TDD primary cell and an FDD secondary cell on the basis of a specific uplink/downlink sub-frame setting related to the TDD primary cell; detecting the downlink control channel in one of the downlink control channel detection sub-frames through the TDD primary cell or the FDD secondary cell while a preset DRX related timer defined by the number of sub-frames operates; and receiving a downlink data signal on the basis of the detected downlink control channel, wherein the downlink control channel detection sub-frames in the FDD secondary cell are sub-frames on the FDD secondary cell, conforming to the location of downlink sub-frames in the specific uplink/downlink sub-frame setting or the location of special sub-frames including a downlink resource having the length identical to or greater than a preset length.