BACKGROUND AND OBJECTIVES: Despite case reports of nosocomial infective endocarditis (NIE), the clinical characteristics of the hospital acquired infective endocarditis have not been investigated in Korea. SUBJECTS AND METHODS: The clinical records of patients with infective endocarditis, treated at Asan Medical Center between January 1989 and December 2003, were retrospectively analyzed. RESULTS: Of the 309 case of native-valve endocarditis, 17 (5.5%) cases were found to be NIE. The mean age of these 17 patients was 51+/-17 years, which included 9 women and 8 men. Staphylococcus aureus was the most frequent causative organism of NIE in 11 cases (65%), of which nine (82%) had methicillin-resistant strains. The prevalence of right-sided vegetation in NIE was higher than that of community acquired infective endocarditis (CIE)(29 vs. 10%, p<0.05); however, left-sided vegetation was observed in more than 70% of patients with NIE (12/17). Surgeries, with or without wound infection (59%) and insertion of a central venous catheter (29%), were the two most common possible sources of NIE. In hospital mortality was significantly higher in patients with NIE than in those with CIE (47 vs. 11%, p<0.001). CONCLUSION: Patients with NIE, which comprises a minor portion of those with infective endocarditis, show unique clinical characteristics in terms of causative organisms, risk factors, sites of vegetation and in-hospital mortality.