Disclosed are a method for mutually transmitting or receiving a downlink signal by a terminal and a base station in a wireless communication system and a device for supporting the same. More particularly, disclosed are a method for transmitting or receiving a signal and a device for supporting the same, in which when a subcarrier interval rapidly changes in a continuous time area, such as a multi-media broadcast multicast service single frequency network (MBSFN), a receiver can more reliably receive a signal (for example: a data signal) transmitted in a resource area where the subcarrier interval has rapidly changed.