Disclosed is a noise suppressor in which a noise signal detected by a first detector (1 a ) is inputted to an adaptive filter (2) and a FIR filter (3). An output signal of the adaptive filter is reproduced by a speaker (5). The reproduced signal by the speaker (5) and a noise signal from a noise source are detected by a second detector (1 b ). The detected signal by the second detector is band-limited by a filter circuit (6) and sent to a LMS computing circuit (4). The LMS computing circuit (4) updates a coefficient of the adaptive filter (2) so as to minimize an output signal (e'(n)) of the filter circuit (6) in response to an output signal (r(n)) of the FIR filter (3) and an output signal (e'(n)) of the filter circuit (6).