One embodiment of the present invention relates to a method by which a user equipment (UE) performs ranging in a wireless communication system, comprising the steps of: transmitting a D2D signal in a subframe N by a first UE; receiving the D2D signal in a subframe N+K from a second UE, which has set, as a subframe boundary, a time point at which the D2D signal is received; and measuring, by the first UE, a round trip time (RTT) by detecting a reception time point of the D2D signal transmitted by the second UE.