Background. Type 2 diabetes mellitus (DM) is an important medical, social, and economic problem due to the high prevalence of the disease, which often leads to disability and significantly increases mortality in elderly people. One of the causes of coronary heart disease (CHD) in patients with type 2 DM is autonomic cardiovascular neuropathy, which is characterized by damage to the autonomic nervous system and manifests itself in a varying clinical picture, including silent myocardial ischemia (SMI). The prevalence of SMI among patients with type 2 DM is much higher than in people without it. The purpose was to study the clinical case of a patient with type 2 DM and CHD, raise awareness of the prevalence and influence of type 2 DM on CHD progression by focusing on diagnostic research and treatment strategies. Materials and methods. The clinical case of the detected silent ischemia in a patient with type 2 DM was analyzed. The complaints were as following: high blood pressure, moderate shortness of breath during walking, pain, and numbness of the lower extremities. Anamnesis: type 2 DM over 20 years; endovascular stenting of the right common iliac artery due to obliterating atherosclerosis of the arteries of the lower extremities; hypertension over 10 years; obesity. Based on this data, CHD was suspected. Results. The Holter monitoring revealed rare episodes of reversible ischemic repolarization. ECG demonstrated the deviation of the electrical axis to the left, hypertrophy of the left ventricular myocardium, diffuse violation of repolarization processes. Ultrasound of the heart found aortic atherosclerosis, left ventricular myocardial hypertrophy, a moderate decrease in myocardial contractility. Ultrasound of vessels of the lower extremities showed the signs of obliterating atherosclerosis with decompensation of peripheral blood flow. Coronary angiography demonstrated left coronary artery with critical subocclusions (90 %), right coronary artery with chronic occlusion in the middle segment (100 %). There was established the diagnosis: coronary heart disease (silent ischemia); diffuse stenotic atherosclerosis of the coronary artery (coronary angiography May 2019); arterial hypertension II stage, degree 2; HF II stage; II NYHA; type 2 diabetes mellitus, insulin-dependent, decompensated; obesity I stage; obliterating atherosclerosis of the arteries of the lower extremities (condition after endovascular stenting of the right common iliac artery on January 2018); chronic pancreatitis in remission, peptic ulcer of the duodenum (operated in 1981); chronic cholecystitis in remission. The treatment was prescribed: insulin therapy, nebivolol, eplerenone, candesartan, clopidogrel, rosuvastatin. Coronary artery bypass grafting is recommended. Conclusions. Thereby, timely diagnosis and adequate treatment can avoid complications of type 2 DM and improve quality and lifetime. With type 2 DM, CHD is often masked and remains undiagnosed, leading to complications and death, therefore more attention to such patients is needed.