We present the cases of 3 children with huge undifferentiated sarcoma of the liver who were treated with surgical excision including liver transplantation as an option and adjuvant chemotherapy. All 3 patients were males aged 10, 13, and 15 years old. The size of the tumor was 10, 15, and 20 cm in diameter, respectively. The youngest patient is disease free and doing well 43 months after resection. The 13-year-old patient presented with tumor rupture and underwent operation. The primary tumor and the ruptured tissue fragments were removed and he was given postoperative chemotherapy. The patient is disease free and doing well 52 months after surgery. The oldest patient had an unresectable tumor in the hilar region. Preoperative chemotherapy was given but later discontinued owing to severe side effects. He underwent living donor liver transplantation followed by postoperative chemotherapy. The patient had recurrent tumor 24 months after transplantation that was excised at reoperation. He is doing well and is disease free 18 months after the second procedure. Complete removal of the tumor including total hepatectomy and transplantation when indicated and suitable pre- and/or postoperative chemotherapy is an effective treatment for children with undifferentiated sarcoma of the liver.