Cultured trials lasting 198 days were conducted to determine the physiological effects of dietary vitamin C and E on reproductive performance of the Chinese mitten-handed crabs Eriocheir sinensis, with mean weight of 78. 21 ± 25. 68g, and female broodstocks were fed with four experimental diets of varying composition. The control group was fed with fresh clams. The gonadosomatic index ( GSI) , fecundity, hatchability of eggs, activities of SOD and the content of MDA in the different tissues, were used to evaluate the performance of the crabs fed w ith different diets. The results showed that the fecundity and hatchability of groups 1, 2 and 3 were 3 620 cell#g- 1( body weight) and 83. 03% ; 3 540 cell#g- 1 ( body weight ) and 84. 06% and 3 790 cell#g- 1 ( body weight) and 86. 27% respectively, which were very signif icantly higher than those of group 4 ( 2 490 cell# g - 1 body weight and 29. 28%) ( P < 0. 01) , and tho se of group 5 ( 3 010 cell#g - 1 body weight and 71. 12%) ( P < 0. 05) . The SOD activities in ovaries of groups 1, 2 and 3 were 56. 35Nu#mL- 1, 53. 61Nu#mL- 1 and 39. 87Nu#mL- 1 respectively, significantly lower than those of group 4 and 5 ( P < 0. 05) , and MDA contents were 6. 03nmol#mL - 1 , 5. 65nmol#mL - 1 and 5. 57nmol#mL - 1 respectively. Though the SOD activity in ovaries of group 4 was 79. 25Nu#mL- 1, peroxidation still took place because of def iciency in VC and VE, so MDA content in ovaries of group 4 was high, 23. 18nmol#mL- 1, resulting in very low hatchability of group 4. This experiment demonstrated that VC, VE supplemented in the diet s of female broodstocks can improve the reproductive performance.