Aim To investigate the changes of serum soluble intercellular adhesion molecule-1 (sICAM-1) concentration among healthy smokers, transient ischemic attack (TIA) and cerebral infarct patients and to study the effects of smoking on the occurrence and development of cerebral infarct. Methods The level of serum sICAM-1 was measured by two-layer antibody sandwich enzyme-linked immunosorbent assay (ELISA) in 31 cases of smokers with cerebral infarct and 31 cases of non-smokers with cerebral infarct, 31 cases of smokers with TIA and 25 cases of non-smokers with TIA, 26 healthy smokers and 28 healthy non-smokers. The cerebral blood flow velocities were measured by transcranial doppler (TCD). Results The level of serum sICAM-1 in cases of smokers with cerebral infarct, TIA and healthy smokers were higher than that of non-smokers with cerebral infarct, TIA and healthy non-smokers respectively (P<0.05). The level of serum sICAM-1 was well correlated with smoking index (r=0.428,P<0.01). The blood flow velocity in bilateral MCA increased compared to that before smoking cigarette (P<0.05). Conclusion Smoking evaluates the sICAM-1 level of the health, transient ischemic attack and infarction patients. sICAM-1 is involved in the process of the occurrence and development of cerebral infarct.