A higher performance signal processing module is demanded because of the high sensitivity of fiber-optic sensor probe. Excellent signal processing module is expected have the function of restore the sensor signal and very little to the introduction of noise. In this paper, improved demodulation algorithm is proposed based on the general demodulation algorithm through changing certain parameters of the algorithm aimed to improve the quality of the signal after demodulation. The output signals of scene sensor probe is sampling, sampling data through filtering. By using the improved fiber optic sensor signal demodulation algorithm, the system can fully improve the quality of the signal after demodulation under the premise of maintains the minimum sampling rate.