A 59-year-old man in previously good health had acute, progressive bronchopneumonia and died after a three-week course of illness, despite treatment with various antibiotics. Serologic, microbiologic, and histologic findings indicated infection with both Chlamydia psittaci and Aspergillus fumigatus. Disseminated, invasive aspergillosis sometimes is a complication of chronic respiratory disease, malignancy, or other deficiency of host defenses, but to our knowledge, this is the first report of psittacosis as a coincidental, probably predisposing disease.