Abstract: To explore the growth promotion mechanism of plant extract from grape (Vitis amurensis) seed andsweet wormwoodon Monopterus albus, 2 400 healthy eel fingerlings were randomly divided into five groups. We fed control group with basal feed, and four experimental groups with diets containing respectively 10 gkg-1, 20 gkg-1, 30 gkg-1, 40 gkg-1 mixture, which were extracted from grape seed and from sweet wormwood (Artemisia annua) with a four-to-one proportion. We determined the digestive enzyme activities,blood biochemical parameters of five eel groups after feeding for 100 d in 21~28 ℃. Results show that basal diets with the mixture could improve digestive enzyme, blood glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT)s activities, and total protein (TP)s content; and could reduce blood glucose (GLU) and triglyceride (TG)s contents of eel. Compared with the control group, the above indexes had significant difference (P0.05) when the dosage of the plant extract was 20 gkg-1 or 30 gkg-1, while the above indexes had no significant difference (P0.05) when it was 10 gkg-1 or 40 gkg-1. There was no significant difference between 20 gkg-1 and 30 gkg-1 experimental groups. In conclusion, extract from grape seed and sweet wormwood with a four-to-one ratio, when mixed in diets with dosage 20~30 gkg-1, could increase digestive enzyme activities, regulate blood biochemical parameters, enhance the digestion and metabolic activity of 3 main nutritive materials andimprove the growth of fish.