This is a review of seven patients with pulmonary emboli manifested as high fever (temperature greater than 39 degrees C) seen over a 3 year period by an infectious disease consultant for unexplained fever. The patients' ages ranged from 16 to 81 years. Bed confinement was the underlying condition of all but one patient. Fever resolved with intravenous heparin therapy in three patients and one patient recovered without heparin therapy. Three patients died. Regardless of the degree of fever, pulmonary emboli should be among the list of differential diagnoses in patients with unexplained fever, especially in those who are confined to bed.