A series of 22 cases with a symptom complex characterized by fever, upper respiratory tract inflammation, and leukocytosis were found to have Diplococcus pneumoniae bacteremia. This finding was unexpected, with one exception, and was established primarily because of the thorough evaluation given each patient. Twenty-one patients received antibiotic therapy; one of them developed the complication of meningeal irritation. One patient received no specific therapy. All patients recovered. The clinical pattern and significance of bacteremia caused by D pneumoniae is discussed.