Aim To investigate the relationship between serum concentration of basic fibroblast growth factor(bFGF) and coronary collateral circulation(CCC) and the severity of atherosclerosis. Methods 80 patients with severe coronary stenosis were recruited.The CCC were rated by Rentrop rating system: rate 0(n=26),rate 1(n=22),rate 2(n=18),rate 3(n=14).Serum concentrations of bFGF were measured by ELISA,and the severity of coronary artery atherosclerosis was evaluated by Gensini's score system. Results The serum concentrations of bFGF were 20.75±6.89 ng/L,22.04±5.18 ng/L,27.32±6.14 ng/L and 32.27±12.04 ng/L in patients with CCC rate 0,1,2 and 3 group respectively.The serum concentrations of bFGF was increased with CCC rating(p<0.05).Spearman corelation analysis demonstrated that there was a positive correlation between CCC rating and the serum bFGF concentrations(p<0.01). Conclusions In patients with severe coronary artery disease,serum concertrations of bFGF in groups with better CCC formation were significantly higher than those in groups with bad CCC formation.Serum bFGF concentrations showed a positive correlation with the rating of coronary collateral circulation formation.