An unusual endometrial stromal sarcoma is described in a 50-year-old patient. The distinctive feature of this case is the focal occurrence of sex cord-like pattern and rhabdoid appearance of tumor cells. Rhabdoid cells have an eosinophilic cytoplasm and a vesicular nucleus with a prominent nucleolus. Immunohistochemistry showed positive cytoplasmic staining for both cytokeratin and vimentin, and ultrastructural examination identified tumor cells with abundant cytoplasmic intermediate filaments. To our knowledge, only one case of endometrial stromal sarcoma with this unusual morphological association has been reported in the literature.