To overcome the disadvantages of light intensity difference frequency stabilization, the dithering frequency stabilization for four frequency differential laser gyro is studied in this paper. Based on the principle of laser gyro, the characteristics and difficulties of the dithering frequency stabilization are analyzed, including the low frequency sensitivity, the severe deviation of operating point at inappropriate gyro parameters, the indistinguishable operating mode and the zero shift problem resulting from the frequency precision. The solutions of each difficulty are presented, the design of low noise circuits is the key factor to improve the precision of the dithering frequency stabilization, which will be helpful to the further experimental study.