In a noise suppressor, a noise signal detected by a first detector is inputted to an adaptive filter and a FIR filter. An output signal of the adaptive filter is reproduced by a speaker. The signal reproduced by the speaker and a noise signal from a noise source are detected by a second detector. The signal detected by the second detector is band-limited by a filter circuit and sent to a LMS computing circuit. The LMS computing circuit updates a coefficient of the adaptive filter so as to minimize an output signal of the filter circuit in response to an output signal of the FIR filter and an output signal of the filter circuit.