Dither signal removal is the important work of mechanical dithered ring laser gyro (MDRLG) signal processor. In view of the limitation of present dither signal removal method in fast tracking use, a new method combining dither stripper with FIR filter is proposed in this paper. Results show that the dither signal in gyro count can be attenuated about 75dB after dither stripper, which can be used in the situation that real time angular rate output is needed. The residual dither signal and high frequency noise can be removed by FIR low pass filter，then the performance is improved under the condition of short time delay.