Adenomyosis is a benign uterine disease. Due to the higher incidence of adenomyosis and patients' demands for fertility, high-intensity ultrasound ablation has been widely used in gynecological patients with uterine fibroids and adenomyosis. Ultrasound ablation of lesions can help alleviate symptoms in patients without increasing the incidence of obstetric complications in subsequent pregnancies. High-intensity ultrasound ablation is not considered a risk factor for uterine rupture. However, we describe a case of adenomyosis treated with high-intensity ultrasound ablation presenting with uterine rupture in the third trimester. The patient underwent an emergency cesarean section to deliver the baby successfully and underwent uterine repair surgery. When treating patients with adenomyosis, care should be taken to protect the myometrium, endometrium, and serous layer to reduce the risk of uterine rupture.