Abstract: Objective To explore the relationships between autoantibodies against α1 adrenergic receptors （α1R）, angiotensin Ⅱ type 1 receptors（AT1R） and coronary heart disease in patients with type 2 diabetes mellitus （DM）. Methods From January 2001 to January 2007, a total of 371 DM patients from department of endocrinology at Wuhan General Hospital and department of cardiology at Wuhan Union Hospital were enrolled and divided into DM with coronary heart disease group （n=117） including 77 silent myocardial ischemia patients, 33 stable angina pectoris patients, 9 old myocardial infarction patients and DM without coronary heart disease group （n=254）. Forty age and gender matched healthy individuals served as control group. The epitopes of the second extracellular loop of α1R and AT1R were synthesized and used as antigen to screen the serum autoantibodies by ELISA. 24 h urinary albumin excretion rate （UAER） was also determined by ELISA. The cardiac structure and function was examined by the echocardiography. The risk factors for type 2 DM with coronary heart disease were detected using multivariate logistic regressions. Results The positive rates of the autoantibodies against α1Rr and AT1R were significantly higher in DM patients than in normal control（52% vs 10%, 48% vs 13%, respectively, both P＜0.01）. The positive rates of the autoantibodies against α1R and AT1R were significantly higher in DM patients with the coronary heart disease than without the coronary heart disease（65% vs 44%, 67% vs 39%, respectively, both P＜0.01）. The positive rate of the autoantibody against α1R was significantly higher in DM patients with silent myocardial ischemia than with stable angina pectoris and old myocardial infarction （74% vs 45% and 67% respectively, both P＜0.05）. The positive rate of the autoantibody against AT1R was significantly higher in DM patients with stable angina pectoris than with silent myocardial ischemia and old myocardial infarction （84% vs 64% and 44% respectively, both P＜0.05）. The regression analysis demonstrated that 3 risk factors for coronary heart disease in type 2 diabetes patients were systolic pressure（OR 1.769, 95% CI 0.737-0.973）, autoantibodies against α1R （OR 1.537, 95% CI 1.325-1.886） and AT1R （OR 2.017, 95% CI 2.013-2.019, all P＜0.05）. Conclusion The serum autoantibodies against α1 and AT1Rs are related to the coronary heart disease in type 2 DM patients.