The present invention discloses a method of transmitting a Physical Random Access Channel (PRACH) by a terminal in a wireless communication system. Specifically, the method includes: receiving first information related to a Synchronization Signal Block (SSB) and second information related to PRACH resources; and transmitting the PRACH on a valid PRACH resource among the PRACH resources based on the first and second information. In this case, valid PRACH resource may be a PRACH resource allocated after symbols in which the SSB is received among the PRACH resources included in a PRACH slot related to the second information.