&NA;Angiosarcoma of the colon with epithelioid and histiocytoid features, a malignant counterpart of epithelioid hemangioendothelioma, was observed in a 72‐year‐old man. The disease first manifested as a right cervical mass, with the histologic appearance of malignant, undifferentiated, large‐cell epithelioid neoplasm. Light microscopy of the colonic tumor disclosed angiosarcoma, with active erythrophagocytosis and positive immunoperoxidase reactions to lysozyme, alpha‐1‐antitrypsin, and alpha‐1‐antichymotrypsin. Ultrastructural features of the tumor cells were those of intermediate betwen endothelial and histiocytic cells. The disease took a rapid fatal course with recurrence, peritoneal dissemination, and massive peritoneal hemorrhage. The cause remains unknown.