The Unscented Kalman Filter (UKF) and Cubature Kalman Filter (CKF) are introduced,and ananalysis is made to their similarities and differences.Through Monte-Carlo simulation tests,the characteristics of UKF and CKF under large azimuth misalignment are studied,and the following conclusions are obtained:1) UKF is sensitive to both angular motion and linear motion,while CKF is only sensitive to linear motion;2) Both the incentive of angular motion and linear motion can speed up the convergence of UKF algorithm,but as to the CKF,the incentive of angular motion makes no contribution to the alignment accuracy while the incentive of linear motion can speed up the algorithm convergence;and 3) The CKF algorithm accuracy can be gradually increased with the improvement of the incentive of linear motion.The unique characteristics are helpful for the engineering realization of alignment technology.