A very large left ovarian tumor in a 76 year old woman, on microscopic study, consisted of an epithelial component: both glandular and squamous, and a sarcomatous component: both cartilage and striated muscle. Epithelial and sarcomatous patterns were intermingled in a spindle-cell stroma. Immunohistochemical study revealed, in these spindle cells, cytokeratin-positive anaplastic epithelial structures and vimentin-positive mesenchymal structures. A review of the literature concerning this rare ovarian tumor especially including cases with a immunohistochemical study is added. However, immunohistochemical study does not allow histogenetic interpretation.