Abstract: AIM:To investigate the relationship between the severity of coronary atherosclerosis and left ventricular systolic function (LVSF). METHODS: The study population consisted of 199 consecutive patients who underwent coronary angiography for suspected or known coronary atherosclerosis. The severity of coronary atherosclerosis was defined by Gensini score. Spearman twoway test and partial correlation analysis were used to assess the relation between the quantitative variables. Multivariate stepwise linear regression analysis was employed to explore the relationship between Gensini score and left ventricular ejection fraction (LVEF). RESULTS: Spearman’s correlation analysis indicated that the Gensini score was negatively correlated with LVEF (r=-033, P<0.01) and fractional shortening of the minor axis (r=-032, P<001) Partial correlation analysis showed that Gensini score was also negatively correlated with LVEF (r=-028, P<0.01) and fractional shortening of the minor axis (r=-026, P<001), whereas the disturbant variables were under control. Multiple stepwise linear regression analysis demonstrated that the severity of coronary atherosclerosis was significantly independently associated with LVSF (β=-0378, P<001). CONCLUSION: The severity of coronary atherosclerosis as measured by Gensini score is independently associated with LVSF. There is a distinct direct dosedependent correlation between the severity of coronary atherosclerosis and LVSF.