The bellybutton is watery and smelly, which is commonly due to the following reasons: 1, umbilicitis, umbilicitis is an infectious disease, which is caused by its local long-term non-cleaning, or repeated friction resulting in skin infection, which can generally be treated by local rubbing iodophor, or iodine and alcohol for deiodination, and if necessary, oral antibiotics, or infusion for treatment. If the infection is serious, you need to go to the hospital’s surgery or emergency department for debridement, and then regular drug exchange treatment. 2, umbilical ureteral cyst, which is a congenital disease, is caused by the umbilical ureter is not closed, you need to go to the hospital to perform abdominal CT or abdominal ultrasound, or imaging to clarify, the disease needs to be regular anti-inflammatory treatment first, and then later surgery to cure, otherwise, such as The long-term presence of the disease may lead to intra-abdominal infection and even malignancy.