Aim To investigate the association between the serum cystatin C concentration and clinical severity,coronary lesion severity of coronary heart disease by comparing the cystatin C concentration in different types of coronary heart disease and analysing the relationship between cystatin C concentration and coronary artery lesions.Methods 152 enrolled cases were divided into three groups according to the clinical condition and results of cardioangiography: normal group（54 cases）,stable angina pectoris group（38 cases）,acute coronary syndrome group（60 cases）.98 coronary heart disease patients were divided into single-vessel lesion group（38 cases）,double-vessel lesions group （22 cases）,triple-vessel lesions group （28 cases） and left main coronary artery lesion group（10 cases） according to the results of coronary angiography Coronary heart disease patients were divided into low Gensini score group（32 cases）,middle Gensini score group（33 cases） and high Gensini score group（33 cases） according to the Gensini score of coronary artery lesions.The cystatin C concentration of all patients were tested by immune enhanced turbidimetric method after admission.The association between serum cystatin C concentration and the severity of coronary heart disease was analysed.Results The serum cystatin C concentration of acute coronary syndrome（1.27±0.27 mg/L） was higher than that of normal group （0.98±0.17 mg/L） and stable angina pectoris group （1.11±0.24 mg/L）（P<0.05）,and there was no significant difference between the stable angina pectoris group and normal group（P>0.05）.The serum cystatin C concentration of singe-vessel group,double-vessel group,triple-vessel and left main coronary artery group were 1.18±0.27 mg/L,1.21±0.34 mg/L,1.16±0.26 mg/L,1.23±0.37 mg/L respectively.No significant difference in serum cystatin C concentration was found among different coronary lesion groups（P>0.05）.The serum cystatin C concentration of low Gensini score group,middle score Gensini group and high Gensini score group were 1.19±0.29 mg/L,1.22±0.28 mg/L,1.16±0.31 mg/L respectively.No significant difference in serum cystatin C concentration was found among different Gensini score groups（P>0.05）.Conclusion The serum cystatin C concentration is associated with clinical severity of coronary heart disease,but not associated with the severity of coronary artery lesions.