A node unit of distributed antenna system, the node unit comprises a delay measuring part configured to transmit a first test signal for delay measurement to an upper adjacent node unit and detect the first test signal looped back via the upper adjacent node unit and measure a round trip delay between the node unit and the upper adjacent node unit, and a delay providing part disposed on a signal transmission path through which a second test signal for delay measurement, to be transmitted from a lower adjacent node unit, is to be looped back to the lower adjacent node unit, and configured to provide a delay corresponding to the round trip delay.