Aim To study the distribution of serum Cystatin C and analyze its associated influence factors in patients with coronary heart disease. Methods 384 patients with coronary heart disease who underwent coronary angiography were selected in the study.The concentration of serum Cystatin C was measured by immunoturbidimetry.From the pathogenetic condition of coronary heart disease,the number of diseased vessels,we study the distribution of serum Cystatin C and the impact of their risk factors in patients with coronary heart disease. Results With increase of serum levels of Cystatin C,the pathogenetic condition in patients with coronary heart disease became more serious,the number of diseased vessels increased.Likewise,with the increase of the age,levels of serum Cystatin C in patients had the same trend.Sex,hypertension,diabetes,dyslipidemia,smoking history,family history of coronary heart disease such as these risk factors were not correlated with levels of serum Cystatin C.Multivariate analysis demonstrates that age is the main factor which influences level of serum Cystatin C in patients with coronary heart disease. Conclusions Levels of serum Cystatin C is mainly affected by age and other factors,reflects the pathological changes of coronary artery and may be related to the pathogenetic condition of coronary heart disease.Therefore,it is an important factor that can not be ignored in clinical therapy of coronary heart disease.