Placental site trophoblastic tumor (PSTT) is a rare form of gestational trophoblastic tumor (GTT) that has different behavior in disease process. The hysterectomy is general for PSTT, but hysterectomy is undesirable for patients who wish to remain fertile. We planned to preserve fertility of a young patient by first administering EMA/CO (Etoposide, methotrexate, actinomycin D/cyclophosphamide, vincristine) chemotherapy and then performing an open uterine surgery to remove residual tumor. The patient who attempted primary chemotherapy for PSTT must be undergone a hysterectomy because this conservative regimen showed sign of chemoresistance. We report a case of chemoresistant PSTT with trial to preserve fertility with a brief review of literatures.