A 90 day growth experiment was conducted to investigate the dietary inositol requirement of juvenile Wuchang bream (Megalobrama amblycephala). The fish were randomly divided into six groups: a control group was fed with basal diet, and five treatment groups fed with basal diet supplemented with 100, 200, 400, 800, 1600 mg/kg inositol, respectively. Each diet was fed to triplicate groups of juvenile M. amblycephalawith initial average body weight (3.4±0.07)g. At the end of feeding trial, final average weight (FAW), weight gain rate (WRG) and specific growth rate (SGR) of fish fed diet 400 mg/kg inositol were significantly higher than those of the control (P<0.05); while feed conversion rate (FCR) was significantly lower in the group supplemented with 400 mg/kg inositol (P<0.05). The concentrations of glucose(GLU), cholesterol (TC) and low density lipoprotein (LDL-C) were higher in fish fed 800mg/kg inositol (P<0.05) and concentration of triglyceride (TG) was significantly lower (P<0.05) than that of the control (P<0.05); In addition, the fat content in liver and muscle of the groups supplemented with 400, 800 mg/kg inositol were significantly lower than that of control (P<0.05); wherase crude protein in muscle was significantly enhanced compared with the control (P<0.05). No significant differences were observed in survival rate, hepatosomatic index (HSI), viscerosomatic ratio (VR), fullness coefficient(CF), high density lipoprotein (HDL-C), moisture and ash in muscle (P>0.05) among the different groups. On the basis of SGR and FCR, the optimum dietary inositol requirement of juvenile M. amblycephalawas estimated to be 294.44 mg/kg and 284.85 mg/kg, using broken line regression analysis.