The pain of small stomach distension in boys may be related to acute enteritis, prostatitis, cystitis and other causes. 1. Acute enteritis: due to bacteria and other pathogens invade the intestinal tract, resulting in an acute inflammatory response, which can be manifested as abdominal distension, abdominal pain and so on. 2. Prostatitis: due to the inflammatory reaction caused by bacteria and other pathogens infecting the prostate, acute pain localized in the perineum can occur, which can radiate to the penis, scrotum, abdomen, thighs and other parts of the body. 3. Cystitis: Inflammation of the bladder caused by pathogenic microbial infections such as bacteria or non-infectious factors such as radiation and drugs can be accompanied by abnormal pain in the lower abdomen. It is recommended that boys with small stomach distension and pain go to the hospital in time, clarify the cause of the disease, and standardize the treatment under the guidance of the doctor.