In the pond culture of juvenile Eriocheir sinensis, various factors have frequently led to a high rate of autotomy and limb impairments. This study evaluated the differential effects of cheliped loss with autotomy and ablation on the short-term cellular and biochemical parameters of juvenile E. sinensis. In this study, compared with the crabs before treatment, the total hemocyte counts (THC), granulocyte counts (GC), hemocyte agglutination, phosphatase activity and glucose metabolism levels were significantly increased, while hyalinocyte counts (HC) and total antioxidant capacity (T-AOC) were significantly decreased within 3 h. However, the THC levels, hemocyte agglutination and hemocyte proliferation were significantly higher in the ablation group within 3 h compared to the autotomy group. Moreover, the changes of glucose metabolism and immune-related enzymes activities in ablation groups were later than autotomy groups. The bacterial challenge showed that the mortality rate of the ablation group was significantly higher than that of the autotomy group. Therefore, the observations in this study indicate that compared with the passive trauma response of ablation, autotomy is a congenital, efficient, and active trauma response mechanism, which is of great significance to the survival and growth of E. sinensis.