If a duplicated kidney has an incomplete duplicated ureteral malformation or a complete duplicated ureteral malformation, if the ureter is open to the bladder and there is no comorbidity, the patient usually has no clinical symptoms and is only found by chance during an ultrasound or a comprehensive urological examination. If the duplicated kidney has comorbidities, pyelonephritis, kidney stones, tuberculosis, tumor, hydronephrosis, etc., and is detected during urological examination after having the above symptoms, the above patients need to be treated surgically. In complete double ureteral malformation, the ureter opening is not in the bladder but in the vestibule or vagina. Patients often have overflow urination, nocturia, bedwetting, etc., and often during the day. Patients have normal urination but still have overflow during the normal interval of urination, mainly because the ureteral opening is not in the right position and does not open in the bladder, making urine control impossible. Intravenous urography can detect congenital malformations that require surgical treatment.