Abstract: Laser gyroscope working mode is likely to hop when it works for a long time or the ambient temperature changes greatly. To change the mode of the laser gyro will bring a great impact on it's performance. Based on the analysis to the backscattering properties in the adjacent model of laser gyro, the backscattering intensity is periodic, and there is a strict correspondence between the working mode and backscattering intensity. The laser gyro mode hopping pattern is that if the model of laser gyro jumps in the same model gyro performance before and after does not change significantly, while it jumps in the adjacent model gyro's lock-in will arise and bias will jump, and gyro performance is affected greatly. According to the mode hopping law the reasonable suggestion was put forward, the above conclusions were proved by the experiment.