There are many kinds of Mucorales. Some of them become pathogenic to human and others to animal species. Mucormycosis has got its name because most of identifiable fungi in reported cases have been of the order Mucorales, belonging to following genera : Mucor, Rhizopus, Absidia, etc. Mucormycosis in human is closely related to chronic debiliating disease. Recently we experienced some cases of rhinoparanasal mucormucosis treated with Caldwell-Luc operation and amphotericin B. All of them were elderly patients with diabetes mellitus. We experienced 3 cases of mucormycosis in nasal cavity and paranasal sinus from november 1994 to January 1995.