Lower abdominal pain in the elderly can be caused by prostatitis, appendicitis, pelvic inflammatory disease and other causes. 1. Prostatitis: It is a common disease in men, which can be caused by pathogenic bacterial infection or certain non-infectious factors. As the inflammation stimulates the mucous membrane of the prostate gland, and the prostate gland is located in the lower abdomen, the phenomenon of lower abdominal pain can occur. 2. Appendicitis: it can be caused by the obstruction of the appendiceal lumen, which allows bacteria to multiply in the appendiceal canal, damaging the mucosal epithelium or causing mucosal ulcers, thus leading to appendicitis, which may often be accompanied by pain in the lower abdomen, fatigue, vomiting and other symptoms. 3. Pelvic inflammatory disease: it is a group of diseases caused by infections in the upper reproductive tract of women, mainly including endometritis, salpingitis, tubo-ovarian abscess and pelvic peritonitis. Due to the stimulation of inflammation pelvic inflammatory disease, lower abdominal pain and increased vaginal discharge are the main clinical manifestations. Lower abdominal pain in the elderly can also be seen in other diseases, it is recommended to go to the hospital to clarify the cause of the disease, under the guidance of the doctor for treatment.