Abstract: Edge detection of medical image is important in medical image processing. We suggested an algorithm of medical image edge clone based on clone technique. First of all, we analyzed the principal of clone technique and built mathematical model of clone technique, then we analyzed principal of edge clone, supposed activation gene and constructed weight gene function. We obtained clone function by using duplicating theory. With human visual properties, method of threshold choice in edge clone was suggested. As a result, simulation experiments compare with the result of edge detection of Canny Operator, and demonstrate better edge recognition capability of the algorithm.