Conjoined twinning is a rare congenital malformation, accounting for 1% monozygotic twins. Conjoined twins result if twining is initiated after the embryonic disc and rudimentary amniotic sac have been formed and if division of the embryonic disc is incomplete. Recently we experienced a case of conjoined twins, dicephalus dipus dibrachius, who had died at 3 hours of life, and performed autopsy. Autopsy revealed a total duplication of the heads, spines up to sacrum, small bowels, thymus and lungs. Two hearts existed within a common pericardium.