Placental tumors are rare in pregnancy. They cause nonspecific complications such as polyhydramnios, fetal anemia, fetal thrombocytopenia and cardiac decompensation with non-immunological hydrops fetalis. In the presented case a very large placental hemangioma was connected with polyhydramnios, premature delivery, fetal anemia and thrombocytopenia, maternal serum alpha fetoprotein elevation and congenital lactic acidosis. After delivery a severe state of the newborn was caused by oligovolemic shock. In the course of the disease the neonatal state steadily deteriorated mainly because of sepsis, cerebral hemorrhage and metabolic acidosis despite adequate therapy. The organic acids assessment in the blood serum of a newborn child showed a very strong signal of lactic acid and an increase in parahydroksyfenylolactic acid. Postmortal examination confirmed prematurity, respiratory distress syndrome, sepsis and cerebral hemorrhage. These symptoms probably resulted from the presence of a placental tumor of considerable size of 12 cm and congenital lactic acidosis, which to our knowledge, have not been described in the available literature until now. In conclusion it should be underlined, that there exists difficult to explain relationship between the presence of a placental haemangioma and severe metabolic changes resulting in high mortality and morbidity of the newborn.