Traditional Hough transform for circle detection has several limitations,such as high computation and memory complexity.To solve these problems,we presented a modified Hough transform method based on gradient information and fuzzy theory.First,gradient information was utilized to reduce the computational complexity.Furthermore,edge points were mapped based on fuzzy theory to avoid peak diffusion and false peak.Finally,a post-processing algorithm was designed to remove the false alarms,since Hough transform would neglect the connectivity between points.Experimental results show that the proposed method has many advantages,such as low computational complexity,high detection accuracy,high detection rate,and low false target rate.