Objective: to establish the effectiveness of treatment of patients with severe angina pectoris in combination with diabetes mellitus (DM) of moderate severity, using the selective inhibitor of late sodium current ranolazine. Object and methods of the study. An open prospective study of 29 patients with ischemic heart disease (CHD), stable angina of stress of functional class (FC) III–IV in combination with DM of moderate severity was conducted. Patients were prescribed ranolazine in addition to the main therapy. The effectiveness of the therapy was assessed after 3 and 6 months of treatment. Results. 72.4% of patients suffered from angina pectoris of FC III, 27.6% from FC IV. At the end of the 3rd month, angina attacks were not observed in all patients with angina pectoris of FC III and in 62.5% of patients with angina pectoris of FC IV. The same results were obtained when surveying patients at the end of 6 months of observation. At the end of 3 months of observation, none of the patients noted arrhythmias. 3 months after the start of observation, fasting blood glucose levels decreased in 86.2% of patients, HbA1c levels decreased in 82.8% of patients, and after 6 months, these indicators decreased in all patients. Conclusion. Ranolazine can be recommended for patients with stable angina with arrhythmias. The use of ranolazine may be effective in patients with CHD in combination with type 2 DM. The use of ranolazine significantly affects the quality of life and helps improve patient adherence to treatment.