Background: Little data is available regarding hospitalized patients with nursing home-acquired pneumonia (NHAP). This is unfortunate because there is an increasing number of elderly persons who are living in nursing homes in Korea. The aim of this study was to compare clinical characteristics and treatment responses of NHAP with community-acquired pneumonia (CAP). Methods: Patients with pneumonia who were admitted from eight nursing homes or from their own homes were enrolled between May 2007 and April 2009. Their clinical characteristics and treatment responses were reviewed retrospectively, and differences between the two groups were analyzed. Results: Of 110 Patients with pneumonia, 66 (60%) were from nursing homes and their median age was 84. In the NHAP group, functional performance status was significantly poorer, classical symptoms of pneumonia were less severe, and multi-lobe involvement (on chest radiographs) was more frequent than in the CAP group. Patients with NHAP more frequently showed lymphocytopenia, anemia, hypoalbuminemia, hypoxemia, and elevated blood urea nitrogen on admission. The mean CURB-65 score was 2.2 in the NHAP group, higher than 1.7 in the CAP group (p=0.004), and multi-drug resistant pathogens were also highly identified in NHAP group (39% vs. 10%, p=0.036). The mean duration of antibiotic therapy was greater for the NHAP (12.6 days) than for the CAP group (6.6 days) (p<0.001). The mortality rate was 23% in NHAP group, which was significantly higher than 5% in the CAP group (p=0.014). Conclusion: NHAP should be more intensively investigated because of the higher frequency of multi-drug resistant pathogens and mortality than the CAP.