Caudal regression is a term applied to a syndrome comprising complete or partial agenesis of sacrum and coccyx, often associated with malformation of the lower extremities(most commonly hypoplastic femurs), congenital heart disease, urologic abnormalities, and malformation of the upper extremities. It is estimated that the overall frequency of diabetes in the mothers of such infant is 16%. We report an autopsy case of 6 day old male infant with complete agenesis of the sacrum, coccyx, and L 5 vertebra, associated with transposition of great arteries, ventricular septal defect, and imperforate anus. He also had flexion deformity of both hip joints and equinovarus deformity of both feet. In addition, there were congestion of the liver and leptomeninges, and patchy plumonary hemorrhage. He was born by caesarian section due to polyhydramnios, breech presentation, suspected congenital abnormalities, and maternal preeclampsia, with the birth weight of 3.33kg. Immediately after birth, he did poorly showing Apgar scores of 5 and 7 after 1 and 5 minutes respectively. Blood glucose level was 40 to 55㎎/㎗ through the first 48 hours of age. A mild hypocalcemia and hyperbilirubinemia were noted. In spite of high oxygen therapy, cyanosis and dyspnea persisted, and he died at 6 days of age. The mother was noticed to be diabetic 3 years age, when she fell into diabetic coma after delivery of a dead born at 7 months af gestation. Thereafter, she was managed with diet control and insulin, intermittently. However, after 4th month of this pregnancy, the diabetes was well controlled till delivery.