Aim. To study clinical characteristics of non-ST-segment elevation acute coronary syndrome (NSTEACS) and to assess the quality of medical health in patients with this condition who were treated in the regional vascular centers and primary vascular units from 48 subjects of the Russian Federation in 2009-2012. Materials and methods. The medical records of 68 467 patients with the verified diagnosis of NSTEACS, which were entered in the ACS Register database on January 1, 2009, to January 1, 2013, were analyzed. The investigation included data on patients aged at least 18 years at admission to hospital with a presumptive diagnosis of ACS, myocardial infarction, or unstable angina pectoris in the case histories. The data were introduced from the completed case histories. In the patients with NSTEACS, the risk of hospital and 6-month deaths was calculated using the GRACE scale. In these patients, the risk of bleeding was estimated using the CRUSADE scale. Results. History data on the presence of risk factors for cardiovascular diseases and prior diseases before ACS were collected from 42,000 patients with NSTEACS. The patients' median age was 66 years; males were 60.6% and women were 59.4%. Smokers were 21.7%. 35.1% of the patients with NSTEACS were found to have a family history of early-onset coronary heart disease (CHD). There were a large proportion of patients at high risk for hospital death according to the GRACE scale. In the period 2009-2012, the proportion of patients with NSTEACS at low risk for hospital death decreased from 30.6 to 25.3% and that of patients at high risk for hospital death proportionally increased from 41.2 to 44.9%. Analysis of the risk for 6-month death by the GRACE scale indicated that the proportion of patients at high risk was twice higher than that of patients at low and moderate risks taken together and did not reduce in the analyzed period of time. The patients with NSTEACS at high risk for hospital and 6-month death (2012) amounted to 44.9 and 61.7%, respectively. In this category of patients, the rate of percutaneous coronary interventions was not greater than 9%. There were a considerable proportion of patients at high and very high risk for bleeding during their hospital stay according to the CRUSADE. Conclusion. By and large, the Russian ACS Register assesses the clinical characteristics of patients with NSTEACS, the risk of hospital and 6-month deaths, as well as that of bleedings, the nature of performed drug therapy and generally gives an estimate of treatment compliance by patients with NSTEAC.