Small abdominal pain in boys may be caused by intestinal diseases, urinary system diseases, appendicitis, reproductive system diseases. 1. Intestinal diseases. Lower abdominal pain is mostly seen in intestinal diseases, such as acute enteritis, dyspepsia, colitis, leading to intestinal spasm, which can cause lower abdominal pain. 2. Urinary system diseases. Lower abdominal pain accompanied by urination disorders, such as urinary pain, urinary urgency, urinary frequency, considered related to urinary system diseases, such as urethritis, cystitis, urethral calculi, bladder stones, caused by lower abdominal pain. 3. Appendicitis. Inflammation of the appendix can cause abdominal pain, mainly metastatic abdominal pain, which may lead to lower right abdominal pain. 4. Diseases of the reproductive system. Male reproductive system diseases, such as orchitis, epididymitis, prostatitis, the stimulation of inflammation, may lead to lower abdominal pain. Boys with unrelieved lower abdominal pain are advised to consult a doctor in time to find the cause and actively treat it with the doctor’s advice.