A tumor mass covered with scrotum-like skin on its tip was found on the perineal region of 3-year-old boy since his birth. The mass was diagnosed as congenital lipoma, which was resected, because of its gradual enlargement. Histopathological findings of the tumor indicated perineal lipoma, and the scrotum-like portion was diagnosed as an accessory scrotum. In the Japanese literature, 7 congenital perineal lipomas (6 males, 1 female) have been reported and all male cases except 1 case (no description about scrotum) were accompanied with an accessory scrotum. We conclude that there may be a close relationship between congenital perineal lipoma and accessory scrotum