PURPOSE: To make the calculation quantity for tap coefficient estimation less than that of an echo removing device for obtaining the same characteristics as before by obtaining the echo removing device which has excellent echo cancellation characteristics even when the number of taps of an adaptive filter is small.

CONSTITUTION: A speaker output signal x(k) sent from a terminal 11 to a speaker 12 is sent to the adaptive filter 15 for echo estimation and filtered to obtain a dummy echo signal. A microphone input signal y(k) collected by a microphone 13 has its electric power equalized or made white through a characteristic converting filter 21 and is sent as a signal u(k) to a subtracter 14, which subtracts the dummy echo signal to obtain an error signal e(k). The tap coefficient of the adaptive filter 15 is updated by adaptive algorithm so that the time mean of the electric power of the error signal e(k) is minimized.