Abstract: Objective The clinical and laboratory studies on hemolytic disease of newborn (HDN) of maternal and child ABO blood type incompatibility were discussed, and to provide a more effective prediction of ABO blood group incompatibility HDN detection method. Methods Serological methods were applied from May, 2014 to September, 2016 in our hospital to check the 600 couples' and newborns' ABO and RhD blood type, the postnatal neonatal umbilical cord blood was collected for HDN three trials (direct antiglobulin test, serum free antibody assay and erythrocyte antibody release test), and the indirect antiglobulin assay was used to determine the titer of anti-A (B) IgG in postpartum serum of pregnant women. Results The number of cases of HDN was 357, and the total positive rate was 59.5%; Maternal-husband-neonatal blood type which was O-A-A type had 168 cases (three positive cases in 49 cases, two positive in 7 cases, 49 cases of positive single, a total of 105 cases showed positive, the total positive rate was 62.50%), O-B-B type had 127 cases (71 cases were three positive, the total positive rate was 62.50%), O-AB-A type had 182 cases (three positive cases in 75 cases, two positive in 37 cases, 70 cases of positive single, a total of 112 cases showed positive, the total positive rate was 61.54%), O-AB-B type had 123 cases (three positive cases in 41 cases, two positive in 14 cases, 14 cases of positive single, a total of 69 cases showed positive, the total positive rate was 56.10%), and the total positive rate was O-A-A> O-AB-A> O-AB-B> O-B-B in order from large to small; The incidence of HDN was also increased as the titer of anti-A (B) IgG in postpartum serum of pregnant women increased. Conclusion ABO HDN has a higher incidence, especially when the mother's blood type is O, the most common neonatal blood type is type A, and antibody release test can effectively detect ABO HDN; maternal IgG anti-A (B) antibody titers can be used to assess the incidence of HDN, which is an important clinical significance for the effective prediction and diagnosis of HDN.