Leukocyte recruitment and inflammatory response play an important patho-physiologic role after cerebral ischemia. This study aimed to evaluate whether leukocyte adhesion molecules can predict clinical outcome in patients after ischemic stroke. We prospectively examined serial changes in p-selectin glycoprotein ligand-1 (PSGL-1), macrophage antigen-1 (Mac-1), and lymphocyte function-associated antigen-1 (LFA-1) expression by leukocyte subsets using flow cytometry at various time points in 65 acute ischemic stroke patients and 60 controls. PSGL-1 expression on neutrophils and monocytes was significantly higher from day 1 to 90 after stroke as compared with control subjects (p < 0.05). The expression of monocyte Mac-1, LFA-1, and neutrophil Mac-1 were also significantly increased on days 1 and 7 after stroke than in control subjects (p < 0.05). Neutrophil PSGL-1 expression on day 1 was significantly higher in patients with early neurologic deterioration (END) (p < 0.01). Monocyte Mac-1 expression positively correlated with National Institutes of Health Stroke Scale (NIHSS) scores on admission (p = 0.013, gamma = 0.318). Underlying disease of diabetes mellitus and NIHSS score on admission were independently associated with 3-month outcome. The expressions of leukocyte adhesion molecules on admission are significantly increased in patients with acute ischemic stroke. This study shows that higher neutrophil PSGL-1 expression on admission may imply a higher risk for END and that monocyte Mac-1 expression on admission reflects the severity of ischemic stroke on admission.