The detection method of pests in stored grain is always investigated. The method based on image recognition is often
discussed. With development of computer technology, information processing, pattern recognition, intelligence detection,
detection method based on image recognition develops fast and becomes main direction of grain pests intelligence
detection. This paper puts forward an edge detection algorithm based on grey relation analysis.The importance of
image's edge detection based on grey relation analysis in pests image processing is introduced. At first the reference
series and compare series are defined. Then the relevant coefficients between the reference series and compare series are
calculated to every pixel. Finally, the edge detection is processed and its application in image's of pests in stored grain is
discussed. The examples show that the method can detect the image's edge of pests in stored grain better.