Abstract: A MIMO narrowband Fx-Newton algorithm is proposed, which can extract line-spectrums by narrowband- pass filters and control them independently by multi controllers. Frequency response matrix of secondary path is identified at the center frequency of each band and inverted oittine, and then the secondary path inverse filtering can be achieved by using L×L 2-order filters and lead controllers iterate to the optimal value rapidly and steadily. In addition, the phase shift caused by narrowband filter is compensated to improve the robustness of control system in case of frequency fluctuation. Experiments on the active-passive isolation mounting of 200 kW diesel generator show that, line-spectrums of 10-11 different frequencies can be controlled simultaneously, and the effect on each line-spectrum is 10-35 dB. The algorithm features advantages of little calculation, good stability and higher convergence rate than FxLMS algorithm especially for large eigenvalue spread of secondary path matrix.