Correct segmentation of digital tongue is an important prophase work to establish tongue diagnosis automatic system of traditional Chinese medicine（TCM）

in order to divide tongue image efficiently and accurately

present a segmentation method based on quad-tree and GrabCut.The method uses quad-tree decomposition to divide collected tongue image first

and then uses mean color of similar regional

optimize Gaussian mixture model（GMM） parameters of GrabCut algorithm

finally achieve tongue image segmentation.Experimental results show that this method increases efficiency of tongue image segmentation greatly

and has a good practicability.