The random error of MEMS gyroscope is a key factor affecting the accuracy of inertial navigationwhich restricts the development of inertial navigation.In order to improve the performance of MEMS gyroscope and improve the accuracy of Allan variance identificationthe random drift error of the gyroscope is analyzed by using the improved Allan variance method.On this basisthe random error model of MEMS gyroscope is established by using the time series analysis method.The results show that the method is simple in calculationflexible in modelingand can significantly improve the accuracy of Allan variance calculation and data utilization rate.The time series model is stable and has strong applicability.