Malignant fibrous histiocytoma of soft part is rather common but malignant fibrous histiocytoma of the bone is rarely encountered clinically. Authors present five cases of malignant fibrous histiocytoma with skeletal involvement and discuss their clinical course, x-ray findings and histological features. This tumor has marked tendency for local recurrence and metastasis. Other bone tumors such as giant cell tumor, aneurysmal bone cyst, non ossifying fibroma, osteosarcoma, fibrosarcoma of bone and metastatic cancer can be excluded by several characteristic findings observed in x-rays as well as histopathological features. All information on the patient should be carefully analysed, because it is difficult to decide whether bone involvement is primary or secondary. Four out of five cases definitely originated within the bone.