Abstract: A method for image edge detection is presented based on Deng interrelatedness and the classical Prewitt edge detection operator.The method takes the Prewitt operator as referential sequence,calculates the Deng interrelatedness of the image pixels between the compared sequence and referential sequence in the eight neighborhoods,and detectes the edge according to the Deng interrelatedness.The experimental results show that the proposed method can detect useful information of image edge more accurately and has some anti-noise ability,and also proves that edge extracted by the combined method has more completion and consecutiveness and fewer non-edge points.The method is also applied to edge detection of remote sensing image.