Aim To study the relationship between serum androgen and atherosclerosis in males. Methods 134 male patients in hospital were divided into four groups according to the result of coronary arteriography: single vessel disease group(n=30),double vessel disease group(n=33),triple vessel disease group(n=28),and the control group(n=43).Serum total testosterone(TT),free testosterone(FT),dehydroepiandrosterone(DHEA),serum total cholesterol(TC),triglycerides(TG),low density lipoprotein cholesterol(LDLC),high density lipoprotein cholesterol(HDLC),lipoprotein a(Lpa),fasting blood glucose(FBG),fasting insulin(FIN) level,homeostasis modle assessment insulin resistance(HOMA-IR) and intima-media thickness(IMT) of the carotid wall were detected in all patients. Results Compared with the control group,the coronary artery disease(CAD) group had significantly decrease in serum FT,HDLC(p<0.001) and significantly increase in serum TC,LDLC,Lpa,FIN,HOMA-IR,FBG and IMT(p<0.05).Serum FT was higher in control group than in CAD group(p<0.001);IMT was lower in control group than in each CAD subgroups(p<0.001).As for serum FIN and HOMA-IR,there were significantly differences between control group and CAD subgroups(p<0.001).Serum FBG was significantly lower in control group than in triple vessel disease group(p<0.01).In Pearson relative analysis,IMT had obvious negative correlation with serum FT,HDLC(r<-0.5,p<0.001),while positive correlation with serum FIN,LDLC,and Lpa(r>0.5,p<0.001). Conclusion The IMT in patients with CAD was thicker than that in control group.The serum FT level in men with CAD was obviously lower than that with normal coronary artery.FT may play roles in the formation of the coronary atherosclerosis in males by influenceing the blood lipoprotein,blood glucose and the resistance of the insulin.