In order to improve furtherly the low frequency response ability of the piezoelectric sensor and its signal conditioning circuit and extend the frequency of piezoelectric sensors, through the analysis of the frequency response of the charge amplifier circuit of the piezoelectric sensor,a method for compensation with a digital filter is proposed . Using the piezoelectric sensor calibration for input and output and matlab software,a FIR filter is designed. Through the sensor testing system with the filter in series, the original measured signal is reproduced. The simulation results show that the method makes the working bandwidth of the measurement system expand and the lowfrequency cutoff frequency of the piezoelectric measuring system is reduced furtherly,the goal to reduce the dynamic measurement error is achieved.