Aim of research: to estimate the influence of quercetin on the dynamic of C-reactive protein, course of myocardial infarction and long-term prognosis of patients with myocardial infarction of the right ventricle on the background of Q-MI of the left ventricle. Materials and methods. There were examined 208 patients with myocardial infarction of the right ventricle: the 1 st group - 155 patients on the background of the Q-MI of the posterior wall of the left ventricle, and the 2 nd group – 53 patients with right ventricle MI on the background of Q-MI of the left ventricle of the circular localization, aged 64.11±0.78 years. Quercetin was prescribed from the 1 st day of myocardial infarction: in the 1 st group – in 88 (55.5%) patients, in the 2 nd group – in 32 (60.4%) patients. The concentration of C-reactive protein in blood serum was determined on the 2 nd day of myocardial infarction and in 6 months with enzyme immunoassay analysis using HS-CRP EIA (Vienna, Austria). Follow-up was (30.6±4.5) months. Study endpoints were: cardiovascular death, unstable angina, recurrent myocardial infarction, heath failure hospitalizations and stroke. Results. The therapy by quercetin was accompanied by the reliable decrease of the risk of fatal arrhythmias, early post-infarction angina, manifestations of the acute and chronic heart failure in the acute period of myocardial infarction of the right ventricle. Quercetin prescription was associated with the reliable decrease of the C-reactive protein (р=0.006) levels in 6 months after myocardial infarction. There was established the predictor role of C-reactive protein after 6 months after infarction in the development of recurrent myocardial infarction (11.4%), unstable angina (7.7%) during 30.6 months. The therapy by quercetin in the 1 st group was associated with the decrease of the frequency of recurrent myocardial infarctions (р=0.012), heart failure hospitalizations (р=0.0056) and cases of the cardio-vascular death (р=0.039); in the 2 nd group – with the decrease of cases of unstable angina (р=0.012) and cardio-vascular death (р=0.01) comparing with patients on the standard therapy. Conclusion. Using of the quercetin in addition to the standard therapy in patients with myocardium infarction of the right ventricle is associated with the reliable decrease of cardiovascular events, particularly cardiovascular death, hospitalizations because of unstable angina and heart failure during 30.6 months of observation and positive dynamics of the C-reactive protein in 6 months after myocardium infarction. The level of C-protein in 6 months after myocardium infarction is an additional risk factor of cardiovascular complications during 30.6 months after myocardium infarction of the right ventricle