A method and apparatus for transmitting or receiving a signal in a wireless communication system according to an embodiment of the present invention may comprise: transmitting message A including a physical random access channel (PRACH) and a physical uplink shared channel (PUSCH); and receiving message B on the basis of message A, wherein random access channel occasions (ROs) for transmission of the PRACH are located in a first slot, PUSCH occasions (POs) for transmission of the PUSCH are located in a second slot, and the first slot and the second slot are time-division multiplexed (TDMed) with each other.