This study compared intake of vitamins and antioxidant nutritional status of smokers and nonsmokers, and the effect of supplementation of vitamin C and vitamin E on antioxidant system of smokers and nonsmokers. Subjects were 30 smokers and 30 non-smokers of male university students. They were divided into groups of 10 subjects each one with supplementation for 4 weeks, to investigate the effects of supplementation. Smokers were divided into vitamin C supplement group, vitamin E supplement group and vitamin C and vitamin E combination supplement group, and so were nonsmokers. The supplementation of vitamin C was 500mg and vitamin E was 400IU. There was no significant difference of antioxidant vitamin intakes between smokers and non-smokers, and plasma concentration of vitamin C in smokers was lower than non-smokers (p<0.05). Blood pressure was higher in smokers (p<0.05), with no difference in blood glucose levels, methemoglobin and TBARS, but SOD activity was significantly higher in non-smokers (p<0.001). Vitamin C supplementation resulted in a significant decrease of diastolic blood pressure (p<0.01), systolic blood pressure (p<0.001) and methemoglobin (p<0.001) in smokers. Also a significant decrease of diastolic blood pressure (p<0.05), systolic blood pressure (p<0.05), blood glucose (p<0.05), methemoglobin (p<0.001) and TBARS (p<0.05), with significant increase of SOD activity (p<0.001) were found in vitamin E supplement group. In vitamin C and vitamin E combination supplement group, there was a significant decrease of diastolic blood pressure (p<0.05), methemoglobin (p<0.01) and TBARS (p<0.05). In non-smokers, methemoglobins (p<0.001) of vitamin C supplement group and vitamin E supplement group decreased, and diastolic pressure (p<0.05), methemoglobin (p<0.01) and TBARS (p<0.05) significantly decreased in vitamin C and vitamin E combination supplement group. These results indicated better efficacy of antioxidant supplementation in smokers than in nonsmokers, suggesting that the supplementation of vitamin C and vitamin E might decrease the oxidative stress and various risk factors of smoking-related diseases.