Undifferentiated endometrial carcinoma of the uterus is rare, and is thought to show a poor prognosis. To date, there is no consensus as to the optimal chemotherapy for this carcinoma. We report a rare case of this carcinoma in a patient who was treated surgically in combination with chemotherapy using a regimen designed by us. This chemotherapy consists of tetrahydropyranyl-adriamycin, paclitaxel, and carboplatin. This regimen is called TTJ [tetrahydropryanyl-adriamycin, taxan (paclitaxel), JM-8 (carboplatin)] chemotherapy and showed a marked effect. The patient was a 52-year-old woman with a giant tumor of the uterus measuring 28 x 18 x 13 cm and weighing 3386 g. She underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy and omentectomy, but residual carcinoma remained on the surface of the small intestine. Pathologically tumor tissues comprised the whole uterus except for the uterine cervix and there were tumor tissues in the omentum. She was treated with six courses of TTJ chemotherapy without major side-effects. Currently, she remains alive without metastasis 41 months after hysterectomy. This report describes a rare case of undifferentiated endometrial carcinoma of the uterus and introduces TTJ chemotherapy resulting in the remarkable effect on this carcinoma.