This experiment was conducted to investigate the effects of dietary γ-aminobutyric acid (GABA) on growth performance, serum biochemistry, body composition, digestive enzyme activity, lpl and tor gene expression of yellow catfish (Pelteobagrus fulvidraco). Four isonitrogenous and isolipidic diets were formulated to contain graded levels of GABA (0, 50, 100 and 200 mg/kg of diet) by adding GABA. A total of 480 fish with an initial average body weight of (1.26±0.01) g were randomly divided into four groups with three replicates of 40 fish each, and each group was fed with one of the diets for 56 d. The results showed that: (1) The final body weight, weight gain rate and specific growth rate of the 100 mg/kg group were significantly higher than those of the control group and 200 mg/kg group. The protein deposition rate, fat deposition rate, calcium deposition rate, and phosphorus deposition rate of the 100 mg/kg group were significantly higher than those of the control group, and the feed ratio was significantly lower than that of the control group. (2) The liver-body ratio of the 50 mg/kg group and 100 mg/kg group was significantly higher than that of the control group. Ash in the 200 mg/kg group was significantly higher than in the control group. (3) There were no significant differences in total protein, triglyceride, cholesterol, glucan, urea, aspartate aminotransferase and alanine aminotransferase among the three groups. (4) The gastric lipase in the 100 mg/kg group was significantly higher than in other groups. Trypsin in the hepatopancreas of the 100 mg/kg group was significantly higher than that of the control group. The 100 mg/kg group had a significantly higher level of intestinal lipase than the control and 50 mg/kg groups (P<0.05). (5) The tor gene expression in the hepatopancreas of the 100 mg/kg group was significantly higher than that of other groups. The tor gene expression in the intestine was significantly higher in the 200 mg/kg group than in the other groups. The intestinal lpl gene expression was significantly higher in the 100 mg/kg group than in the other groups. The study showed that the dietary addition of 50-100 mg/kg γ-aminobutyric acid significantly improved the growth performance and body composition of P. fulvidraco , and the dietary addition of 100 mg/kg significantly increased the digestive enzyme activity, lpl and tor gene expression levels. Combined with the comprehensive evaluation of growth, body composition, digestive enzyme activity, lpl and tor gene expression levels, the dietary addition of 50-100 mg/kg γ-aminobutyric acid significantly increased the digestive enzyme activity of P. fulvidraco. The optimal amount of GABA added to the diet of yellow catfish was 100 mg/kg. In summary, adding GABA to feed improved the growth performance, digestive enzyme activity, body composition and nutrient retention of P. fulvidraco, and played a positive role in the growth of P. fulvidraco.