Abstract: This study aims at investigating the effects of replacing soybean oil with rubber seed oil on growth performance, digestive enzyme activity and antioxidant capacity of Asian red- tailed catfish (Hemibagrus wyckioides), and determining the appropriate replacement rate of soybean oil by rubber seed oil. Five isoproteic and isolipidic experimental diets (R0, R25, R50, R75 and R100) were formulated with rubber seed oil replacing 0%, 25%, 50%, 75% and 100% soybean oil in diets, respectively. The feeding trial lasted for 8 weeks. The results showed that: (1) the weight gain and daily gain coefficient of fish fed R25 diet were significantly higher than that of the other diets (P<0.05); (2) the intestinal lipase activity was higher in R25, R50 and R75 diets, compared to R100 diet; the intestinal trypsin activity of R25 diet was significantly higher than that of the other diets; similarly, the hepatic lipase activity was higher in R25 diet compared with fish fed R75 and R100 diets; (3) with the increasing of rubber seed oil replacement level, the hepatic alanine transaminase, aspartate transaminase and glutamyl transpeptidase activities firstly increased and then decreased, the highest values were observed in R25 diet; the hepatic glutamate dehydrogenase activity of R100 diet was significantly lower than that of R0 diet; (4) the plasma peroxidase of R100 diet was significantly lower than that in R25 and R75 diets; similarly, the plasma total antioxidant capacity of R100 diet was significantly lower than that of R25 and R75 diets; the hepatic malondialdehyde content was significantly higher in R100 diet compared with fish fed the other diets. These results indicate that replacing 25%-75% soybean oil with rubber seed oil has no obvious negative effect on feed utilization and antioxidant capacity, and replacing 25% soybean oil is beneficial to improve the growth performance, but total replacement markedly depresses the antioxidant capacity of Hemibagrus wyckioides.