Objective To study the plasma antioxidant vitamin status in patients receiving enteral nutrition(EN) or parenteral nutrition(PN) after upper gastrointestinal surgery.Methods One hundred and twenty patients who underwent upper gastrointestinal cancer surgery were randomized into EN and PN group.The plasma vitamin A,vitamin E and ?-carotene levels pre-and post-operation and one week after clinical nutrition supplement were studied.Results Vitamin A and ?-carotene levels decreased significantly after surgery(P=0.03 and P=0.01,respectively).Vitamin E decreased 10 weeks after the nutrition,and it was significantly lower in the EN group than in the PN group(P0.05).Conclusions A decrease of antioxidant vitamins is induced by surgery and vitamin E is recommended to be given in nutrition supplement patients,especially in the patients receiving EN.