According to one embodiment of the present invention, a method by which a terminal for supporting device to device (D2D) communication relays a D2D signal comprises the steps of: transmitting, by the terminal, a D2D signal to be relayed to a neighboring terminal; and relaying a signal transmitted by the neighboring terminal, on the basis of the information on the D2D signal, wherein the information on the D2D signal includes information on D2D power, and the information on the D2D power can be determined by considering a reception power difference between D2D signals transmitted on mutually adjacent frequencies.