The assessment of risk factors for in-hospital mortality in patients with infective endocarditis is important for identifying variables associated with treatment regimens, aiming to improve outcomes. Early identification of high-risk patients may contribute to better outcomes through timely medical and surgical interventions. Objective: to study the clinical characteristics and risk factors associated with in-hospital mortality among patients with infective endocarditis. Materials and methods. A retrospective single-center study was conducted, which included clinical data of 311 consecutive patients from January 1, 2019, to October 22, 2021, at the Amosov National Institute of Cardiovascular Surgery of the National Academy of Medical Sciences of Ukraine. The primary outcome of the study was in-hospital mortality among patients with infective endocarditis. Clinical and laboratory data, as well as the results of echocardiographic examinations and postoperative complications were recorded and statistically analyzed. Results. The overall in-hospital mortality rate was 13 cases (4.2 %), including 6 (1.9 %) patients with infective endocarditis who died at the preoperative stage despite medical treatment. Postoperative in-hospital mortality accounted for 7 cases (2.3 %), 298 patients (95.8 %) underwent successful surgery and were discharged under the supervision of a cardiologist in their locality. A univariate analysis of preoperative clinical and laboratory characteristics revealed the following risk factors for in-hospital mortality among patients with infective endocarditis at the preoperative stage: fever (p = 0.021), mechanical ventilation (p < 0.001), acute kidney injury (р < 0.001), heart failure (р < 0.001). Similarly, a univariate analysis of intraoperative and postoperative clinical and laboratory characteristics revealed risk factors for in-hospital mortality among patients with infective endocarditis at the postoperative stage to be aortic cross-clamping time (p = 0.010), duration of cardiopulmonary bypass (p = 0.006), ultrafiltration volume (p < 0.001) and N-terminal pro-B-type natriuretic peptide level (p = 0.017). Conclusions. Our study demonstrated that risk factors for in-hospital mortality among patients with infective endocarditis included fever, heart failure, respiratory failure, acute kidney injury, and duration of cardiac surgery. These findings underscore the necessity for a multidisciplinary approach to the treatment of infective endocarditis.