Primary malignant peripheral nerve sheath tumor (MPNST) in a young female patient, not associated with neurofibromatosis type-I is extremely rare in the liver. A 33-year-old female was admitted with a right flank pain for a weak. The CT scan showed 12.5-cm-sized mass located at the right hepatic lobe. At laparotomy, about 20.0-cm-sized mass was on the right hepatic lobe with attachment to right diaphragmatic pleura. Right hepatic lobe and adherent part of diaphragmatic pleura were resected. On histology and immunohistochemistry, it was diagnosed MPNST. Adjuvant radiotherapy for the right diaphragmatic pleura and adjuvant chemotherapy with adriamycin, ifosfamide and cisplatin were sequentially performed. The prognosis of MPNST is generally poor and it is associated with a highly aggressive course of recurrence, metastases, and death. Our case is probably a first report about combination therapy.