The experiment was conducted to study the ability of digestion and enzymolysis in 4 kinds of protein in common feed ingredients of Coreius heterodon in vitro. Two hundred wild Coreius heterodon with average weight of 146.81 g were temporarily fed 24 h for eliminating the contents of digestive canal. The intestine and hepatopancreas were took out for the preparation of the digestive juice sample. Fish meal, soybean meal, rapeseed meal and cottonseed meal were digested by enzymatic hydrolysis in vitro. The results showed that compared with the intestine, the hepatopancreas of Coreius heterodon possessed better enzymolysis ability for protein in feed ingredients. Moreover, the enzymolysis ability of middle intestine was the highest and the lowest in post intestine. The enzymolysis rate of fish meal (8.551 mg/h) in intestine within 0-4 h was higher than that of soybean meal, rapeseed meal and cottonseed meal, but the enzymolysis rate of soybean meal (13.110 mg/h) was the highest in hepatopancreas (P<0.05). The average enzymolysis rate of amino acid of the 4 kinds of protein in feed ingredients was 10.75, 10.03, 9.05, 7.36 mg/h, respectively. In conclusion, Coreius heterodon had a good ability to digest fish meal and soybean meal.［Chinese Journal of Animal Nutrition, 2010，22（2）:335-340］