Gynandroblastoma is a rare ovarian tumor that is composed of both Sertoli cells and granulosa cells. Only 23 cases have been reported in the literature, and recurrence has never been described. We report the first case of a recurrent gynandroblastoma along with its molecular analysis and immunohistochemical studies. A 49-year-old Gravida 0 woman with a 10-year prior diagnosis of ovarian-mixed stromal tissue tumor (well-differentiated Sertoli cell and granulosa cell tumor) and staging laparotomy, presented now with a retroperitoneal mass and an elevated inhibin level. CT scan was suspicious for recurrence. The patient had no prior adjuvant therapy. The histomorphological features of the recurrent tumor had both Sertoli cell and granulosa cell tumor. The molecular analysis of both primary and recurrent tumor showed minor genetic instability in the 17q12.2 gene locus with no dedifferentiation or progression, which is consistent with a low-grade tumor. The immunohistochemical staining profile showed positivity for CD99, inhibin, calretinin, and vimentin; focal positivity for cytokeratin AE1/AE3 and negative for EMA and melan-A. All the previously mentioned immunostainings support the diagnosis. We report the first case of a recurrent gynandroblastoma 10 years after initial presentation along with its molecular analysis and immunohistochemical studies.