To investigate the relationship between morphological characters and body mass of adult Chinese mitten crabs Eriocheir sinensis， 19 morphological characters were measured and compared among E. sinensis with different body weights by quantitative and multivariate analysis， and the hepatopancreas index （HSI）， gonadosomatic index （GSI）， meat yield （MY） and total edible yield （TEY） of these crabs were compared either. The results showed that： （1） There were 13 and 11 significantly different characteristics detected in male and female E. sinensis respectively， and the values of morphological characteristics related to the length of carapace significantly increased with E. sinensis body weights increasing， but the values related to carapace width and feet length significantly decreased with E. sinensis size body weights increasing. （2） The results of principal component analysis （PCA） revealed that the polts represents different-sized individuals were relatively separated with only a slight overlap between group， indicating a quite different morphology of the individuals with different sizes. （3） Significant difference were detecte in tissue indices among different-sized crabs， and the larger crabs （Male≥300 g； Female≥150 g） had significantly lower values of GSI but significantly higher values of HSI， MY and TEY than the smaller ones. All in all， different-sized E. sinensis had significant differences in morphological characteristics and tissue indices， and they showed a significant negative correlation with GSI， which would provide a valuable reference for commercial and broodstock crabs selection.