Healthcare-associated pneumonia (HCAP) is a newly identified condition, and epidemiologic studies in Japan are still limited. We retrospectively observed patients with HCAP and community-acquired pneumonia (CAP) who were hospitalized between December 2004 and March 2005, and compared their disease characteristics. A total of 34 patients (14 with HCAP and 20 with CAP) were evaluated. Of the patients with HCAP, seven (50%) were hospitalized for at least 2 days in the preceding 90 days and five (35.7%) resided in a nursing home or extended care facility. Compared with patients with CAP, patients with HCAP were older, had more complications, including central nerve diseases, had greater disease severity, but lower serum albumin level. More methicillin-resistant Staphylococcus aureus, Pseudomonas spp., and anaerobes were isolated from patients with HCAP than from those with CAP. Conversely, more Streptococcus pneumoniae was detected and more penicillin was used in patients with CAP. This study provides additional evidence that HCAP should be distinguished from CAP and suggests the pathogenesis and therapeutic strategy for HCAP may be similar to those for hospital-acquired pneumonia.