An error path characteristic model correction control unit determines the deviation of the phase of an actual transfer function from the phase of an error path characteristic model, from a cross correlation between an error signal output from a microphone and a signal in which the error path characteristic model is applied to a noise cancellation sound to be output and a cross correlation between the error signal and a signal in which a transfer function having a phase characteristic deviating by +90 degrees from the phase characteristic of the error path characteristic model is applied to the noise cancellation sound. The error path characteristic model correction control unit then corrects the error path characteristic model so that the determined deviation is reduced to ±90 degrees.