This paper presents an efficient grayscale image colorization scheme that mainly consists of three components including YUV-transformation,sample sequence redundancy removal and space relativity based pixel matching.The low-complexity YUV-transformation technique can effectively remove the correlation existing in RGB color space.A sample sequence redundancy removal strategy is proposed to cut down the pixel matching time of the whole target image.A space relativity based pixel matching algorithm is employed to improve searching efficiency and accuracy.The experimental results show that while obtaining results similar to Welsh algorithm′s performance,the proposed efficient grayscale image colorization scheme can save time from 50% to 70% for the colorization process.