An apparatus and a method for effectively mapping a reference signal for vehicle-to-everything (V2X) communication in a wireless communication system are provided. A transmission terminal performing the V2X communication includes a processor generating sidelink control information (SCI) and a transceiver transmitting the generated SCI to a reception terminal through a physical sidelink control channel (PSCCH) and a physical sidelink shared channel (PSSCH). A decision on whether to allocate a demodulation reference signal (DMRS) of the PSSCH and the PSCCH to the same orthogonal frequency division multiplexing (OFDM) symbol is made based on a number of subchannels and at least one sized thereof