Malignant granuloma syndrome is defined as a progressive non-healing ulceration and granulomatous lesion localized in the nasal cavity, paranasal sinus or pharyx. Within the wide range of name of malignant granuloma syndrome, the commonest are malignant midline granuloma, Wegener's granulomatosis, polymorphic reticulosis and malignant lymphoma. In 1982 Aozasa and Inoue reported several cases of malignant histiocytosis presenting as lethal midline granuloma, characterized by systemic, progressive, invasive proliferation of atypical histiocytes and their precursors. Common symptoms of malignant histiocytosis are fever, lymphadenopathy, hepatosplenomegaly, pancytopenia and eventually leading to death within 6 months. We reported 3 cases with clinical features of the malignant granuloma, finally diagnosed as malignant histiocytosis.