Abstract: The random drift of fiber optic gyro is a important factor direct affected the accuracy of the optical for the fiber gyro inertial navigation system and the drift of the fiber optic gyro random is the important factors influencing the system initial alignment precision.In the paper,the theory of wavelet analysis was in-depth studied,it use multiple wavelet filtering methods to the inertial navigation system,Compare with the results of the filter and select out the best wavelet filter method for the engineering application.The Allan variance analysis method is used for performance evaluation.The wavelet filter method is applied to initial alignment test,and the results is tested.Itverify the best wavelet filter method and it has high engineering significance.