Genistein (4',5,7-trihydroxyisoflavone) is the most abundant isoflavone found in the soybean that exhibits an anti-inflammatory effect. The present study was designed to examine the effects of genistein on expression levels of hemolysate-induced proinflammatory and adhesion molecules in SD rat brain microvascular endothelial cells (BMECs). Genistein treatment attenuated hemolysate-induced nuclear factor-kappa B (NF-kappaB) p65 translocation in BMECs. In addition, genistein suppressed the expression levels of tumor necrosis factor-alpha (TNF-alpha), monocyte chemoattractant protein 1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1), but not vascular cell adhesion molecule-1 (VCAM-1). The inhibitory rate of 50 pM genistein for TNF-alpha, MCP-1 and ICAM-1 was 65.4%, 60.5% and 54.9% respectively. These inhibitory effects of genistein on proinflammatory and adhesion molecules were not due to decreased BMEC viability as assessed by MTT test. Taken together the present study suggests that genistein suppresses expression levels of hemolysate-induced pro-inflammatory and adhesion molecules in cerebral endothelial cells.