We describe a case of disseminated penicilliosis in a patient with the acquired immunodeficiency syndrome. Penicillium marneffei was cultured from the blood, bone marrow, sputum, stool, and skin; the yeast forms were demonstrated in skin and bone marrow biopsy specimens. To our knowledge, this is the first reported case of disseminated penicilliosis described in a patient with the acquired immunodeficiency syndrome. The differential diagnosis with Histoplasma capsulatum is reviewed.