This experiment was conducted to study the effect of replacement of fish meal by fermented mulberry leaves on the growth, lipid metabolism and antioxidant capacity of largemouth bass[with the initial weight (10 g)]. Four isonitrogenous and isoenergetic diets (CP 42%, GE 18 MJ/Kg) were formulated to contain different levels of fermented mulberry based upon the basal diet to replace fish meal 0 (D₁), 15% (D₂), 30% (D₃) and supplement EAA based on 30% (D₄). After 8 weeks, the results showed that final weight (FW), specific growth rate (SGR), viscera somatic index (VSI) and hepatopancreas somatic index (HSI) were decreased significantly when the replacement ratio of fish meal by fermented mulberry was 30%, and supplement crystalline amino acids (CAA) could improve the growth of largemouth bass obviously. There were no significant differences in protein efficiency ratio (PER), feed conversion ratio (FCR), feeding rate (FR), condition factor (CF) and whole body general composition for each test group. The largemouth bass serum of CHO, TG, HDL-C and LDL-C were decreased observably but the ratios of HDL-C/CHO and HDL-C/LDL-C showed the opposite trend. The LDL-C decreased as fermented mulberry ratio increased. Superoxide dismutase (SOD) activities increased significantly as fermented mulberry ratio increased, but malondialdehyde (MDA) decreased markedly. Results of above show that a suitable percentage of fermented mulberry replacement of fish meal has no effect on the growth of largemouth bass. Too high replacement levels would inhibit the growth of largemouth bass, but could improve the lipid metabolism and antioxidant capacity of largemouth bass. Supplement of essential amino acids can improve the utilization of fermented mulberry, and promote the growth of largemouth bass.