Objective To investigate the clinical significance of CD7 expression in childhood acute myeloid leukemia(AML).Methods A retrospective analysis was performed on 60 children with AML admitted to Jiangxi Province Children's Hospital from October 2016 to December 2020.According to the results of immunophenotyping,the children were divided into CD7 positive(CD7+)group and CD7 negative(CD7-)group.The clinical characteristics,immunophenotype and treatment effect of the two groups were compared.Results Among 60 children with AML,18 cases were CD7+,and the positive rate was 30.00%,mainly M2 and M5,the expression rate of M2 was 55.56%,which was higher than that of other subtypes.The CD7+ group had significantly higher white blood cell count and bone marrow blast granulocyte count than the CD7-group(P<0.05).There were no significant differences in platelet count,hemoglobin,lactate dehydrogenase,creatinine and other laboratory indicators between the two groups(P>0.05).After 1 course of standard induction chemotherapy,the CD7+ group had a significantly lower complete remission rate than the CD7-group(P<0.05).There was no statistically significant difference(P>0.05)in the overall survival rate and disease free survival rate between the two groups of patients at 1 year and 2 years.Conclusion Compared with CD7-children,the peripheral white blood cell count and bone marrow blast cell count of CD7+ children were significantly higher,and the complete remission rate of induction chemotherapy was significantly lower.The expression of CD7 antigen has a significant predictive value for the poor prognosis of children with AML,which may provide new ideas for the treatment strategy of children with AML,and lay the foundation for further exploring the mechanism of CD7 in the development of AML.