Abstract: An image segmentation method based on the velocity feature vector of moving target was proposed. According to moving vector sameness of the pixels in a target image block, the velocity vector was estimated by inter frame image matching in an image sequence. Block matching algorithms were utilized in the matching process. All image blocks that have the same motion vectors were clustered and a moving target was identified. It was proved that the method is effective and feasible to segment the moving target from complicated background and has the better anti noise ability.