Two cases of disseminated mucormycosis in patients with underlying hematological disease are described. Both patients presented with fever and pulmonary infiltrates which did not respond to empirical treatment with broad-spectrum antibiotics and antifungal agents, and in both patients there was rapid progression with a fatal outcome. All cultures were negative and the diagnosis was made postmortem. A review of the literature revealed only three recent reports of successful treatment of disseminated mucormycosis. Survival correlated with control of the underlying disease and early diagnosis based on histological examination of biopsy specimens from suspected lesions. Therapy consisted of surgical debridement and amphotericin B. Standard therapeutic schedules need to be defined for this infection.