McKusick-Kaufman Syndrome (MKS) is an autosomal recessive multiple malformation syndrome characterized by hydrometrocolpos (HMC) and post-axial polydactyly (PAP). We report a case of MKS who was transferred to the neonatal intensive care unit of Seoul National University Children’s Hospital on the 15th day of life for further evaluation and management of abdominal cystic mass. And she had revealed HMC, PAP, soft palate cleft, hydronephroses, hypoplastic right kidney, uterine didelphys with transverse vaginal septum and low type imperforated anus. She was temporarily treated with sonogram guided transurethral aspiration. She was being followed up at the outpatient clinics of Pediatrics, Pediatric Surgery and Pediatric Urology. Jump back operation and plastic operation were also planned. But follow-up for monitoring was lost after 49 days of age. Recently, we could contact her again and she was recommended for operation for low type imperforated anus, soft palate cleft, and polydactyly. Current clinical care should include monitoring for the complications of Bardet-Biedl syndrome (BBS) as the published literature contains no evidence of features allowing reliable differentiation of the two syndromes in the neonatal period. Therefore, We planned to do molecular genetic analysis and monitoring for the complication of BBS, such as retinal disease, learning disability, obesity, and renal failure.