Matching is a classical problem in stereo vision.To solve the matching problem that components cannot continue growing on the occlusions region and repetitive patterns,an improved seed growth method is proposed.The method obtains a set of interesting points defined as initial seeds from a rectified image.Through global optimization the seeds and their neighbors can be selected into a match table.Finally the components grow with the matching points and create a semi-dense map under the maximum similar subset according to the principle of the unique constraint.Experimental results show that the proposed method in the grown process can rectify some errors in matching.The semi-dense map has a good performance in the occlusions region and repetitive patterns.This algorithm is faster and more accurate than the traditional seed growing method.