Chlamydia pneumoniae, previously known as Chlamydia psittaci strain TWAR, causes both upper and lower respiratory tract infection. We report the first two cases of culture-positive Chlamydia pneumoniae lower respiratory infection in Singapore. Both patients had underlying fibrosing alveolitis and presented with a history of prolonged productive cough and fever. Chlamydia pneumoniae was isolated from the bronchoalveolar lavage fluid in the absence of other pathogens. The patients responded clinically to three weeks of oral doxycycline therapy. Infection due to Chlamydia pneumoniae should be considered when a patient with community-acquired pneumonia fails to respond to the usual standard antimicrobial therapy.