Objective   To explore the cardiovascular risk factors and clinical features of coronary lesions in male patients with premature coronary artery disease (CAD).     Methods   A total of 448 male patients with CAD confirmed by angiography were divided into two groups by age: premature CAD (n=145

55 y) and mature CAD (n=303

≥55 y). The risk factors of premature CAD and the clinical features of coronary lesions were compared statistically. The independent risk factors in premature CAD were screened by multi-factor analysis. The extent and severity of angiographic CAD were diagnosed by the number of narrowed vessels and the CAD Gensini cumulative index. Cardiovascular risk factors included hypertension

smoking

type 2 diabetes mellitus

hemoglobin

total bilirubin

plasma lipid

plasma uric acid

plasma fibrinogen

and family history of ischemic cardiovascular disease.     Results   The percentage of family history of ischemic cardiovascular disease

the history of smoking

the level of total cholesterol (TC)

triglyceride (TG)

hemoglobin (HGB) and plasma fibrinogen (Fig) in premature CAD group were higher than those in mature CAD （P0.01

P0.05）. The proportion of lesion in the single coronary artery in premature CAD group was higher than that in mature CAD （P0.01）. The proportion of lesions in the left circumflex branch (LCX) and the right coronary artery (RCA) and the CAD Gensini cumulative index in premature CAD were lower than those in mature CAD （P0.01

P0.05）.     Conclusion   Family history of ischemic cardiovascular disease

history of smoking

and levels of TG

HGB

and Fig may be the independent risk factors in premature CAD. Higher proportion of single vessel lesion and slight lesion can be found in premature CAD patients than that in mature CAD patients.