In order to solve the problem that the reliability of visual navigation is restricted by motion blur under high dynamic environment,a novel non reference motion blurred image quality assessment algorithm based on improved structural similarity is proposed.Firstly,the re blurred image is produced by the original blurred image with the same blurred direction.Then two images are divided into 8×8 blocks,and find the edge block,and then structural similarity of corresponding edge blocks in original blurred image and re blurred image.Finally the blur estimation of the blurred image is obtained by the different weights of the edge block’s structural similarity index.The experimental results show that the proposed approach can obtain good performances,and the algorithm is more sensitive than traditional MSSIM algorithm.