Disseminated infection caused by Fusarium moniliforme is described in a 32-year-old granulocytopenic man with malignant lymphoma being treated with cytotoxic drugs and corticosteroids. Infected skin denuded by antecedent severe varicella-zoster infection was the probable source of fungemia. F. moniliforme grows rapidly on common mycological media as a lavender- to violet-colored mold at 25 to 37 degrees C. Its aerial hyphae produce fusoid macroconidia and characteristic fusiform microconidia in chains. The morphology of hyphae in tissue closely resembles species of Aspergillus and is not diagnostically specific. Morphological characteristics which distinguish cultures of F. moniliforme from other medically important species of Fusarium are discussed.