If the belly button is smelly, it is due to umbilicitis, which is usually caused by scratching the belly button with dirty hands or bathing water entering the belly button, causing inflammation of the belly button, which results in smelly secretions. For navel infections with smelly secretions, you need to go to the hospital for surgery, and with the help of the doctor, flush the navel with saline and metronidazole, rinse the navel with secretions, disinfect with iodophor, apply pressure bandages with sterile gauze, and at the same time take cephalosporin antibiotics and other symptomatic treatments, and change the medication every 3 days or so to observe the changes in the navel. If the discharge increases or if there is redness and swelling, it is considered that the infection is aggravated and requires incision and drainage. You should practice good hygiene, do not scratch your belly button with dirty hands, use sterile cotton swabs to expel foreign bodies from your belly button if necessary, pay attention to a light diet, and eat less spicy and stimulating food.