Abstract: Since the navigation performance and robustness of the integrated navigation system which combines the BeiDou and inertial navigation system are poor,the paper proposes a new algorithm under uncertainty noise interference, which bases on the attenuation factor and noise weighted adaptive Kalman filter technology. The paper first conducts simulation experiments with Matlab,comparing the traditional Kalman filter technology to verify the effectiveness of the new algorithm.Then the data postprocessing experiment of UAV is carried out. The results show that the improved adaptive filter algorithm can effectively increase the interference immunity of the integrated navigation system, thus improving the navigation performance and robustness.