A ranging system and ranging method are provided. The ranging system includes a transmission signal generator which generates a transmission signal, which is transmitted from a transmission device to a reception device; a correction signal generator which converts the transmission signal, which is processed in the reception device and re-input to the transmission device, into a correction signal; a reference signal generator which generates a reference signal, an overlap detector which detects an overlap region between the correction signal and the reference signal; a time calculator which calculates a transmission time of the transmission signal; and a distance calculator which calculates a distance between the devices using the transmission time. The method includes generating a transmission signal; transmitting the transmission signal to a reception device and receiving the signal back again; producing a correction signal; detecting an overlap region between the correction and reference signals; calculating a transmission time; and calculating a distance between the transmission and reception devices.