Complete reduplication of the urinary bladder is a rare con d ition. The patient here reported is 26-month-old girl, who visite d our hospital with chief complaint of anomalous external genitalia. Two external genita l i a were present at distance of about 10 cm, and further examinations revealed multiple malformations. These anomalie s consist in the urinary tract, female genital organs, gastrointestinal tract and skeletal system. In the low er urinary tract, complete reduplication of the urinary bladder was found. It was characteristic that each bladder had its own urethra and received one ureter. In the upper urinary tract left pelvic kidney was also demonstrated, w h ile right kidney was normal in position. Vesicouretera l refluxes were apparent bilaterally. Bilateral imperforated anuses with righ t perineal fistula were seen and roentgenologic examination gave a finding of duplicated rectum, but colonic duplications were not clearly demonstrated. Two appendices had been removed in the course of surgical repair for umbilical hernia at her age of 3 months in another hospital. Diastasis of the pubic bone, separated sacrum and a half vertebra with a rib were observed as the skeletal anomalies. Perineal ano p lasty was performed for a difficulty in defecation. Because of an immaturity and dysfunction of the urinary bladder, which are shown in the cystometrogram and electromyogram of the external vesical sphincter, cosmetic and urological reconstruction is now withheld. Thirty-one cases, i n cluding our own, of the complete reduplication of the urinary bladder were reviewed in the literature and discussed.