A female was born at 36⁺⁵ weeks of gestation with a birth weight of 2,120 g. Apgar score was 7 at 1 minute and 9 at 5 minutes. Shortly after birth, tachypnea, chest retraction, and a severe build-up of oral secretions were noted. Her blood type was A⁺ and initial hemoglobin was 17.5 g/dl. Her mother was A⁺ blood type. Ampicillin/Sulbactam and gentamicin were started empirically. At 8th day of admission, laboratory results showed hemolytic anemia. Exchange transfusion was performed along with intravenous immunoglobulin and hydrocortisone. After 2 days, the patient’s clinical and laboratory conditions improved. Column hemagglutination assay revealed that the patient’s hemolysis was due to ampicillin/sulbactam.