A 68-d feeding trial was conducted to investigate the effects of replacing fish oil with dietary wheatgerm oilon growth, body composition, serum biochemical indices, and lipid metabolic enzymesin juvenile Cynoglossussemilaevis Günter [initial body weight, (3.70±0.01) g]. Six isonitrogenous and isoenergetic experimentaldiets were formulated with 0, 20%, 40%, 60%, 80%, and 100% replacement of the fish oil with wheat germ oil.Survival rate was similar among the fish fed the different diets (P>0.05). Specific growth rate and the protein efficiencyratio decreased with increasing replacement level; the 80% and 100% replacement groups were significantlylower than the control group (P<0.05), whereas the feed conversion ratio showed a reverse trend [80% and100% replacement groups were significantly higher than control group (P<0.05)]. No significant differences wereobserved in the viscerosomatic index, hepatosomatic index, or condition factor (P>0.05). Liver fat content increasedwith increasing replacement level, whereas whole fish fat content decreased; whole fish water content inthe 80% and 100% replacement groups was significantly higher than that in the control group (P<0.05). Muscleand liver C18: 3n-3 and C18: 2n-6 concentrations increased significantly with increasing wheat germ oil level (P<0.05),whereas C20: 5n-3 and C22: 6n-3 concentrations decreased significantly (P<0.05). No differences in serum glutamic-pyruvate transaminase, glutamic-oxaloacetic transaminase, or alkaline phosphatase (P>0.05) were detected.Serum triglyceride and total cholesterol levels decreased with increasing replacement level; the 80% and 100%replacement groups were significantly higher than the control group (P<0.05). No significant difference was foundin serum lysozyme activity (P>0.05), but serum malondialdehyde content decreased. Hepatopancreas lipoproteinlipase, hepatic lipase, fatty acid synthase, and intestinal lipase activities increased with increasing replacementlevel. These results suggest that wheat germ oil can replace 60% of fish oil without significantly affecting growthof juvenile C. semilaevis Günter. Wheat germ oil promoted body fat metabolism and inhibited lipid peroxidationbut significantly changed fatty acid composition in tissues.