The present invention discloses an operation method of a terminal and a base station in a wireless communication system supporting an unlicensed band and a device for supporting same. The present invention discloses an operation method of a terminal and a base station and a device for supporting same, according to one specific embodiment, wherein the method is based on signaling, to the terminal, whether or not the base station is occupied by each channel access procedure (CAP) subband through downlink control information (DCI) including slot format information for one or more slots.