Disclosed are a method for transmitting and receiving downlink control information (DCI) in a wireless communication system and a device for same. Particularly, in a method for receiving downlink control information by a terminal in a wireless communication system, the method can comprise the steps of: receiving first DCI from a base station via a first downlink control channel on the basis of a first transmission time interval (TTI); and receiving second DCI from the base station by means of control channel information via a second downlink control channel on the basis of a second TTI, wherein the first DCI comprises the control channel information indicating one or more merge levels relating to the reception of the second DCI among a plurality of predetermined merge levels.