Cesarean scar gestational trophoblastic disease (GTD) is very rare. With relaxation of China's fertility policy, the number of cases has increased. The authors admitted two patients with hydatidiform moles in 2005; ultrasound indicated a nidus located in a previous cesarean scar. Both patients underwent uterine artery embolization (UAE) followed by suction curettage or hysteroscopy and were subsequently diagnosed with cesarean scar gestational trophoblastic neoplasms, and chemotherapy was administered. The prognosis of both patients is good. The authors found that the trophoblastic cells on cesarean scar were more likely to cause myometrium infiltration and result in a high risk of bleeding. Ultrasound, UAE, and hysteroscopy play important roles in its diagnosis and treatment. When a cesarean scar gestational trophoblastic neoplasm is considered, chemotherapy should be promptly administered.