Abstract: A no-reference image quality assessment method based on bottom-up visual attention mechanism and top-down image sharpness metric is proposed for the blur image quality evaluation.Firstly, the color, intensity and orientation feature maps are calculated based on the human visual attention mechanism, and then the saliency region of the image is obtained by the winner-take-all competition. Secondly, the image of saliency region and the background region are evaluated using no-reference image sharpness evaluation method, and the final image quality index can be obtained by the combination of the above two results.The radial blur images produced in the forward motion imaging and the Gauss fuzzy images in the Live database evaluation are evaluated using the proposed method respectively.Experiment results can prove that the correlation coefficient between the results of our method and the subjective one is larger than 0.98 for the radial blur images.The method can be used for evaluating the blur image subjectively.