Mucormycosis is an uncommon opportunistic fungal infection that may develop in immunocompromised patients with conditions such as diabetes mellitus, leukemia, lymphoma, or human immunodeficiency virus (HIV), or after transplantation with immunosupperessive therapy. We report a case of gastric perforation caused by a mucormycosis infection in a patient with acute myelogenous leukemia (AML). The patient was treated successfully with gastrectomy and the aggressive use of intravenous amphotericin B. He is still alive 1 year after his operation.