The present paper describes a case of cerebral neoplasm presenting histological-immunohistochemical characteristics of malignant rhabdoid tumor (MRT) and ultrastructural features of both MRT and rhabdomyosarcoma (R). MRT was first described as an aggressive neoplasm of unknown histogenesis of the kidney, then many other sites of onset were reported, including the central nervous system. However, it has been shown that other tumors of known histogenesis can mimic histologic and ultrastructural features of MRT. On the basis of our findings we agree with authors who support the notion that extrarenal MRT has often a different histogenesis from MRT of kidney, and it probably is a 'phenotypic' entity rather than a distinct pathologic entity.