Disclosed is a method for a first terminal, which supports a sidelink, to transmit signals in a wireless communication system. Specifically, the method may comprise: a step for receiving a sidelink synchronization signal (SLSS) from a second terminal; a step for acquiring information about a subframe boundary time point for timing synchronization, and information about a propagation delay time; and a step for transmitting a sidelink signal to the second terminal on the basis of the subframe boundary time point and a timing advance (TA) that is twice the length of the propagation delay time.