Abstract Objective This study aimed to assess the probable relationship between icter in neonates with ABO incompatibility hemolysis and UGT1A1 gene polymorphism. Study Design There were 65 ABO hemolytic disease of the newborn (HDN) neonates of full term in the study group and 82 non-ABO HDN neonates of full term in the compared group. We tested the UGT1A1 gene mutation of neonates of ABO HDN and non-ABO HDN. We compared the incidence of hyperbilirubinemia between neonates with and without UGT1A1 mutations in the ABO HDN and non-ABO HDN, to determine the relationship between icter in neonates with ABO HDN and UGT1A1 gene polymorphism. SPSS 13.0 were used to analyze those two groups' data. Results There was statistically significant difference of the serum bilirubin level between the Gly71Arg homozygous and no mutation group in the ABO HDN patients (p < 0.05). When hyperbilirubinemia was defined as serum bilirubin concentration >342 μmol/L, the incidence of hyperbilirubinemia between patients of UGT1A1 and non-UGT1A1 mutations in the ABO HDN group was significantly different (p < 0.05). But in the non-ABO HDN group, no significant difference was found. Conclusion Individuals with Gly71Arg homozygous contributed to their hyperbilirubinemia in ABO HDN patients.