Abstract: Aiming at the problem of the blurred direction detection of small-scale motion blurred image, a new algorithm for blurred direction detection was presented by analyzing the cause of detection error. Firstly, we refined the bright lines with median filter in the twice Fourier spectrum to eliminate the spectrum noise. Secondly, we chosen mid-value as a threshold to transform the spectrum to a binary image. And then we removed the cross bright line and bright speck to heighten the direction feature. Finally, we projected all bright spots onto the straight lines of all slopes through the center of the binary image, and calculated the maximum of projection to estimate the blurred direction. Furthermore,the effectiveness of the algorithm with the blue scale of degraded image varied from 3 pixels to 10 pixels was verified by simulation. Experiments demonstrate that the estimation accuracy of this method is higher than other methods in smallscale motion blurred image.