Abstract: The methods to detect mango weight and surface bruise by computer vision technology were investigated in this paper. The algorithm for determining the image area was analyzed and the correlation between mango weight and its image area was developed. Test results showed that the accuracy of weight grading was 96 % and 92 % for Guixiang mango and Zihua mango respectively, and the accuracy of surface bruise grading was 76 % and 80 % respectively.