Aim To investigate the expression and distribution of basic fibroblast growth factor(bFGF)in atherosclerosis(As) plaque of arteriosclerosis obliterans(ASO) cases. Methods The protein level and area of bFGF in As plaque and normal artery of human were studied by means of immunohistochemistry. Results The expression of bFGF had a high level in As plaque and was mainly distributed in the area where there were plenty of vascular smooth muscle cells,in constrast the expression of bFGF was very low in normal arterial(0.033 7±0.012 5 vs 0.014 5±0.001 7,p<0.05). Conclusion It suggested that the higher expression of bFGF was related to the pathogenesis of As and ASO.