Malignant fibrous histiocytoma appears to be emerging as one of the most common soft tissue sarcomas of late adult life. Cytologic features of a metastatic malignant fibrous histiocytoma in the lung, examined by fine needle aspiration, are reported. Essentially, four cell types in various proportions were observed: spindled cells, pleomorphic giant cells, undifferentiated mesenchymal-type cells and rare signet ring "lipoblast-like" cells. There also were several huge hyperchromatic and often bizarre naked nuclei.