Pyometra, the accumulation of purulent material in the uterine cavity, is a rare gynecological condition whose etiology is impaired drainage of the uterine cavity. It is uncommon in premenopausal age and occurs mainly in older and postmenopausal women. Clinical signs of pyometra are vaginal discharge, postmenopausal bleeding, and lower abdominal pain. An 87-year-old woman was admitted to our emergency department with abdominal pain, fever, and vomiting. The results of physical examination revealed rebound tenderness and muscular rigidity in the lower abdomen. Ultrasonography demonstrated free fluid in the abdomen, and percutaneous aspiration revealed that this fluid was purulent. A computed tomography scan showed a large amount of free fluid in the abdominal cavity and a uterine myoma. The patient underwent emergency laparotomy due to acute abdomen. During the laparotomy, a 2x1 cm perforation was seen at the fundus of the uterus. The patient underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy. A culture of the pus grew Escherichia coli. Histopathological examination revealed degenerative uterine myoma with no evidence of malignancy. Pathological results indicated myometrial suppurative inflammation along with neutrophilia and necrosis. Pyometra is a rare event; however, it must be considered when investigating acute abdomen etiology. Because pyometra involves abscess formation, drainage and evacuation of the uterine cavity while leaving a drain in the cavity and dilating the cervical canal is the main treatment protocol. In cases of perforation, hysterectomy is the treatment choice; however, with concomitant diseases in older patients, immediate surgery is related to important morbidity and mortality risks.