Leukocyte behavior in the cerebral microvasculature following vessel occlusion has not been fully elucidated. The purpose of this study was to investigate the effects of cilostazol on leukocyte behavior (rolling and adhesion) in murine cerebral microvessels following transient bilateral carotid artery occlusion using intravital fluorescence microscopy. Three groups of mice were assigned: sham group(n=8), ischemia reperfusion(I/R) group(n=6), I/R+cilostazol (CZ) group (ischemia reperfusion after cilostazol administered orally 30 mg/kg) (n=8). Ischemia was induced of 15 min of bilateral common carotid artery (CCA) occlusion using microvascular clips. Leukocyte labeled with 0.05%acridine orange were intravenously administered and their behavior was investigated at 3 and 6 h, through a parietal lesion window made just after the ischemic period. The number of rolling or adhering leukocyte was expressed per square millimeter per 30 seconds. Numbers of rolling and adhesion leukocyte at 3 or 6 h after reperfusion in I/R group were significantly increased compared to sham group and numbers of rolling and adhesion leukocyte in the CZ group were significantly inhibited at 3 or 6 h after reperfusion compared to the I/R group in pial veins (P<0.05) and in pial arteries (P<0.05). Cilostazol inhibited leukocyte-endothelial interactions following cerebral ischemia and reperfusion.