Aim To investigate the protective effects of Jiawei Buyang Huanwu decoction on vascular stenosis and on the nitric oxide(NO) system after iliac artery were injured by balloon in diet-induced atherosclerotic rabbits. Methods 24 male New Zealand albino rabbits were equally randomized into control group, model group and drug group. The iliac arteries of the rabbits in the latter two groups were subjected to balloon injury. Four weeks later, serum NO synthases (NOS) activity and endothelial nitric oxide synthase (eNOS) level was assayed, endothelial hyperplasia, eNOS protein and mRNA expression were observed in injured iliac artery. Results Optical microscope revealed narrowed vascular lumen, thicken intima and numerous arteriosclerotic plaques in the model group compared with the control group, whereas the vascular lumen and intima thickness remained basically normal in drug group.The serum NO level and total NOS activity were higher in drug group than that of model group.Immunohistochemistry and RT-PCR results showed that eNOS protein and mRNA expression was stronger in rabbit iliac artery of drug group than that in model group.Conclusion Jiawei Buyang Huanwu decoction can lessen intimal hyperplasia and vascular stenosis in iliac artery injury rabbits, and this effect is possibly related with that Jiawei Buyang Huanwu decoction activated the NO system.