Monosex cultivation of Chinese mitten crab is a potentially promising aquaculture method. Customizing gender-specific diets based on the nutritional requirements of males and females is a crucial prerequisite for precise feeding. This study employed a 2×2 factorial experimental design （2 diets × 2 genders） and conducted an 80-day aquaculture experiment in outdoor pond enclosures. The research investigated the effects of gender-specific fattening diets on the cultivation performance， physiological metabolism， and biochemical composition of pre-adult male and female Chinese mitten crabs （Eriocheir sinensis）. The experiment consisted of four groups： males fed with male-specific diet （MM）， males fed with female-specific diet （MF）， females fed with female-specific diet （FF）， and females fed with male-specific diet （FM）. Each group had four replicate enclosures. The results show that： Feeds had no significant effect on the growth， survival rate， yield， and feed conversion （P>0.05）. However， gender had a significant impact on growth， yield， and feed conversion at day 80 （P<0.05）； The hepatosomatic index（HSI） and gonadosomatic index（GSI） of the FF group were higher than those of the FM group， and the GSI difference was significant on the 80th day （P<0.05）. The total fat content in the hepatopancreas was significantly higher in the FF group than in the FM group （P<0.05）. However， there were no significant differences in conventional biochemical components in edible tissues between the dietary groups （P>0.05）； Concerning antioxidant and immune indicators， the glutathione peroxidase（GSH-Px） activity in the hepatopancreas was significantly higher in the MM group than in the other groups （P<0.05）， while the FF group had the highest total superoxide dismutase（T-SOD） activity in the hepatopancreas. Both diet and gender factors significantly influenced acid phosphatase（ACP） activity in the serum （P<0.05）； Regarding protein and lipid metabolism， the MM group had the highest trypsin activity in the hepatopancreas and the lowest lipase activity. The FF group had significantly higher triglyceride（TG） content in the hepatopancreas （P<0.05）. The FF group had the highest levels of total protein（TP）， TG， total cholesterol（TC）， low-density lipoprotein cholesterol（LDL-C） and high-density lipoprotein cholesterol （HDL-C） in the serum. In conclusion， male crabs fed fed male-specific diet demonstrated enhanced antioxidant and immune capacity， promoting protein deposition； female crabs fed female-specific diet accelerated ovarian development and increased triglyceride deposition in the hepatopancreas.