The clinical characteristics of 26 patients with community-acquired pneumonia due to Chlamydia pneumoniae as the only identified pathogen who required hospitalization were evaluated. Most patients (18) had reinfection based on serological results. The mean age of the patients was 55 years (38 years, patients with primary infection; 63 years, patients with reinfection), and the gender representation was equal. Generally, illness was mild and associated with limited temperature elevation and nonspecific symptoms. The presence of comorbid illnesses and the requirement of supplemental oxygen therapy were the most common criteria for hospital admission.