Aim To evaluate the clinical and coronary angiographic features in elderly patients with type 2 diabetes mellitus combined with coronary heart disease. Methods A total of 133 cases confirmed by coronary angiograph were divided into two groups according to the status if they had combined with type 2 diabetes mellitus or not. Then the study was carried out by case control analysis of the clinical and the data from angiograph. Results High triglyceride, low high density lipoprotein cholesterol and low left ventricular election fraction levels were found in the group of type 2 diabetes mellitus combined with coronary heart disease. Also in this group, the lesions were mainly found in left main coronary artery and all three vessels. The abnormalities of wall motion was more common in this group and the collateral circulation was more abundant than group without typE₂ diabetes mellitus. Through Logistic regression analysis, advanced age, high triglyceride and low high density lipoprotein cholesterol levels were confirmed to be independent risk factors. Conclusions In elderly patients with type 2 diabetes mellitus combined with coronary heart disease, the lesions were mainly found in left main coronary artery and all three vessels. Advanced age, high triglyceride and low high density lipoprotein cholesterol levels played an important role in the severity of coronary artery lesions in this kind of patients.