The leukocyte count and concentrations of(s)ICAM-1 and(s)VCAM-1 in smokers were investigated. The subjects were 96 persons (31 smokers and 65 nonsmokers) hospitalized for a complete health checkup examination. There were no differences between the two groups for background factors (age (nonsmokers, 56.2 ± 9.2 vs smokers, 52.6 ± 11.3)gender ratio (m/f)(nonsmokers, 47/18 vs smokers, 24/7) and drinker ratio (+/-) (nonsmokers, 45/20 vs smokers, 26/5)). For smokers, the average number of cigarettes smoked daily, smoking period(ys) and Brinkman Index were 21.4 ± 10.4, 26.2± 14.5 and 584.2 ± 476.9, respectively. In smokers, total leukocyte count (l μ 1) (6371.0 ± 1303.4 vs 5063.1 ± 1279.1,(p)<0.0001), and(s)ICAM-1 concentration (ng/ml) (202.6 ± 64.0 vs 163.0 ± 60.8,(p)<0.01) were higher than those in nonsmokers. No significant difference in the(s)VCAM-1 concentration was shown between the two groups. Items showing large correlation coefficients with the number of cigarettes smoked daily were the total leukocyte count (r = 0.45,(p)<0.0001) and(s)ICAM-1 (r = 0.36,(p)<0.0001). In smokers,(s)ICAM-1 showed correlation with the total leukocyte count (r = 0.42,(p)<0.05) . We conclude diat the leukocyte count and(s)ICAM-1 concentration in healthy smokers are higher than those in nonsmokers.