Abstract: In image segmentation, threshold selection is crucial.For traditional Otsu's algorithm exists threshold deviation cause poor image segmentation problem, a kind of fuzzy judgment Otsu image segmentation algorithm has been proposed. Though the process of Otsu's threshold fuzzy judgment,by the gravity method for searching the threshold to get a result of segmenting image better. Experimental results show that the proposed algorithm can get better result compared with one-dimensional Otsu's algorithm and two-dimensional Otsu's algorithm.