We are reporting a rare case of hemolytic disease of newborn with weak D antigen in child. A 3rd order male child of G3P3A0 mother was admitted at 8th h of life with jaundice. Blood group of both mother and child were A Rh D negative. Baby's direct coombs test was positive. Weak D antigen was positive in baby. Hematological parameters showed all the signs of ongoing hemolysis, and the bilirubin level was in the zone of exchange transfusion. Exchange transfusion was done. An intravenous immunoglobulin was given to child after that. Mother had a history of first normal healthy male child with O Rh D positive blood group. Second male child expired on 3rd postnatal day due to bilirubin encephalopathy that had A Rh D negative blood group with positive direct coombs test.