The present invention provides a method for transmitting and receiving a downlink signal between a terminal and a base station in a wireless communication system supporting an unlicensed band, and a device supporting the method. As a specific example, the present invention includes a method for: transmitting and receiving a physical downlink control channel (PDCCH) signal in an unlicensed band so that a base station and a terminal transmit and receive system information associated with a particular synchronization signal/physical broadcast channel (SS/PBCH) block; and, based on the PDCCH signal, transmitting and receiving a PDSCH signal including the system information.