Effective treatment for community-acquired pneumonia (CAP) requires administration of appropriate empirical therapy based on etiologic, clinical, and radiological fea- tures. However, in Korea, CAP is poorly characterized, and data on viral CAP are particularly sparse. Therefore, im- proper use of antibiotics is common, and is detrimental the potential for development of bacterial. Thus, we investigated clinical and radiological findings for discrimination of viral CAP from bacterial CAP. Etiologic, clinical, and radiologi- cal data from 467 patients with CAP at Chungbuk National University Hospital from October 2010 to September 2011 were analyzed retrospectively. Viruses were identified in 23 cases (11.4%); the influenza virus A was the most common virus detected (N=18, 25.4%), followed by the respiratory syncytial virus A (N=14, 17.9%). Bacteria were identified in 48 cases (23.8%); Streptococcus-pneumonia was the most common (N=24, 25.5%), followed by Staphylococcus aureus (N=20, 21.3%). Depending on hospitalization time, the fol- lowing significant differences were observed between viral and bacterial CAP: on admission, (1) high fever (≥ 38.5°C), (2) purulent sputum, (3) white blood cell count, (4) C- reactive protein levels, (5) and bilateral lung involvement on chest X-ray were higher in bacterial CAP; and at discharge, (1) duration of high fever and (2) radiologic improvement within three days were higher in viral CAP. Regarding sea- sonal patterns, both viruses and bacteria have been identi- fied with relative frequency in the winter season. This study described the etiological, clinical, and radiological findings of viral and bacterial CAP. Conduct of additional large- scale, prospective investigations will be required in order to improve the appropriate treatment of CAP.