Abstract: Partially blurred images caused by motion or out of focus are common in life, we need to detect and segment blurred image region when doing some multimedia analyzing tasks. As for the problem of blurred region detection and segmentation of partially blurred images, we propose a method based on singular value decomposition and image matting is presented in this paper. Making use of the different changes of image blurred regions and clear regions under a low-pass filtering , partially blurred image is firstly partitioned into patches and each image patch is re-blurred by a Gaussian function, then a trimap is got after comparing the singular value feature difference of the patches to distinguish blurred regions and clear regions. Secondly, a image matting technique is combined with the trimap to automatically segment blurred regions from the partially blurred images. Experiments show that this method can detect and segment the blurred regions accurately.