Abstract: An echo canceling system and an echo canceling method are provided, which can deal with the case where there are a plurality of echo paths and respond to the variation in echo arrival times. An echo canceling method to be applied to a full-duplex communication system includes detecting a respective echo arrival time of one or plural echo paths based on a reference signal and an echo signal, calculating as many pseudo-echo signals as the detected arrival times, overlapping the calculated pseudo-echo signals to obtain an overall pseudo-echo signal, and subtracting the overall pseudo-echo signal from the echo signal. A FFT processing is performed with respect to the reference signal and the echo signal, and a similar canceling processing is carried out using an amplitude spectrum alone.