A 36-year-old man, five years after bone marrow transplantation for aplastic anemia, was admitted with myonecrosis of the forearm after he had immersed his hand in sewage water several days prior to his admission. Blood cultures and specimens taken from the necrotic tissue of the arm all grew Aeromonas hydrophila. Following extension of the infection, the patient underwent amputation of the arm but ultimately died of cerebral mucormycosis. The epidemiology of Aeromonas infections is discussed and the literature of Aeromonas myonecrosis is reviewed.