Background: Uterine tumor resembling ovarian sex-cord tumor (UTROSCT) is a considerably rare gynecological tumor which has undetermined pathogenesis but with distinct polyphenotypic immunohistochemical expressions. According to the limited cases and follow-up information in the relevant literature, most of the tumors exhibit indolent or low malignant clinical course and the outcomes of the patients with the tumors generally have a good ending. But for the subset of UTROSCT with aggressive characters, the outcomes of the patients with recurrent neoplasm were not always satisfactory.Case presentation: In this case report, the recurrence of neoplasm was reported in the pelvic cavity after 53 months of surgery and irregular follow-up. The recurrent neoplasm grew in an invasive manner, and the arrangement of the recurrent neoplasm cells was closer, the nucleus atypia is more pronounced, and the cells demonstrated a more briskly mitotic activity (10 mitotic figures/10 HPF). The Ki67 index increased significantly and the expression of P53 was positive. For the recurrent tumor, both the clinical characteristics and the histological morphology of the recurrent neoplastic cells showed a more malignant behavior. The patient received a palliative resection of pelvic mass and bilateral oophorectomy, and she died of intestinal obstruction caused by the recurrent disease 9 months postoperatively.Conclusions: UTROSCT should be recognized as a definite malignant potential neoplasm. Based on the clinicopathological, immunohistochemistry parameters and the reviewed previous literature, we speculated that significant mitotic activity and large tumors (≥10 cm) were of value for the aggressive characters of the tumor, and the recurrence of the tumor might lead to a poor prognosis.