Aim To study the association between obstructive sleep apnea syndrome(OSAS) and cardiovascular risk factors in the male elderly. Methods 582 male elderly subjects were recruited and underwent standard polysomnography(PSG).Body mass index(BMI),neck circumference,waist circumference,hip circumference,waist to hip ratio,blood pressure,fasting blood glucose(FBS),high sensitivity C-reactive protein(hs-CRP),total cholesterol(TC),high density lipoprotein cholesterol(HDLC),triglyceride(TG),low density lipoprotein cholesterol(LDLC),free fatty acids(FFA) were measured.With respect to apnea-hypopnea index(AHI),the subjects were divided into OSAS patients and controls,furthermore,according to the value of AHI,OSAS patients were classified into mild,moderate and severe OSAS ones. Results OSAS patients had higher BMI,neck circumference,waist circumference,hip circumference,systolic blood pressure,FBS,hs-CRP,TG than controls.HDLC,average oxyhemoglobin saturation and minimum oxyhemoglobin saturation during sleep time was lower in OSAS patients than controls.The prevalence of metabolic syndrome was higher in OSAS patients than in controls.Severe OSAS patients had higher BMI,neck circumference,waist circumference,hip circumference,average and minimum oxyhemoglobin saturation during sleep time,however lower HDLC than mild and moderate patients.In Spearman's correlate analysis,OSAS and AHI were positively correlated with BMI,neck circumference,waist circumference,hip circumference,systolic blood pressure,FBS,hs-CRP and inversely correlated with HDLC.In multiple stepwise regression analysis,neck circumference was independently correlated with OSAS.Conclusion OSAS in the male elderly is associated with cardiovascular risk factors,which maybe induce the increased morbidity and mortality of cardiovascular disease.