Objectives To study clini- cal and coronary angiographic findings in patients with both coronary heart diseases (CHD) and type 2 diabe- tes mellitus (T2DM). Methods 215 patients with CHD confirmed by coronary angiography were involved in this study. The patients were divided into two groups: 74 CHD patients with T2DM (mean age 64.7 ± 8.2 years, male/female 47/27), and 141 CHD pa- tients without T2DM ( mean age 66. 2 ±9. 2 years, male/female 100/41 ). The clinical features and the data from selective coronary angiographies were com- pared between type 2 diabetic and non - diabetic CHD patients. Results Compared to non - diabetic CHD patients, the patients with both CHD and T2DM suf- fered more from acute myocardial infarction, silent is- chemia and severe arrhythmias ( P < 0. 01, P < 0. 05 ) , and had higher serum triglycerides and apo - lipoprotein B, along with increased serum uric acid (P < 0. 01, P < 0.05), increased left ventricular end diastolic diameter ( P < 0. 01 ) , and decreased left ventricular ejection fraction ( P < 0. 001 ). Compared to non - diabetic CHD patients, the patients with both CHD and T2DM suffered more from triple vessel disease (P < 0. 01) , severe coronary artery stenosis, complete occlusions and diffuse lesions ( P < 0. 001). Conclusions Se- vere clinical manifestation, left ventricular dysfunction, diffuse or complicated lesions of coronary arteries weremore common in patients with both CHD and T2DM, it suggests that the type 2 diabetic CHD patients have poor prognosis. Objectives To study clini-cal and coronary angiographic findings in patients with coronary heart diseases (CHD) and type 2 diabe-tes mellitus (T2DM). Methods 215 patients with CHD confirmed by coronary angiography were involved in this study. The patients were divided into two groups: 74 CHD patients with T2DM (mean age 64.7 ± 8.2 years, male / female 47/27), and 141 CHD paients without T2DM (mean age 66.2 ± 9. 2 years, male / female 100 / 41). The clinical features and the data from selective coronary angiographies were com- pared between type 2 diabetic and non-diabetic CHD patients. Results Compared to diabetic CHD patients, the patients with both CHD and T2DM suf-fered more from acute (P <0.01, P <0.05), and had higher serum triglycerides and apo - lipoprotein B, along with increased serum uric acid (P <0.01, P < 0.05), increased left ventricular end diastolic diameter (P <0.01), and decr Compared to non-diabetic CHD patients, the patients with both CHD and T2DM recovered more from triple vessel disease (P <0.01), severe coronary artery stenosis, complete occlusions and diffuse lesions (P <0.001). Conclusions Se- vere clinical manifestation, left ventricular dysfunction, diffuse or complicated lesions of coronary arteries were more common in patients with both CHD and T2DM, it suggests that the type 2 diabetic CHD patients have poor prognosis .