Abstract: Objective  To evaluate the relationship between risk factors and childhood leukaemia.
Methods  WanFang database, CNKI, DAYI database, PubMed database were searched to obtain the related articles about the relationship between risk factors and childhood leukaemia, retrieval time until August 20, 2019, the research results were analyzed with revman 5.3 software. 
Results  A total of 25 case-control studies on risk factors of childhood leukemia were included, including 4 307 cases in the case group and 5 159 cases in the control group. Meta-analysis results showed that the OR and 95% confidence interval（CI）, of the first three factors with a correlation between childhood environmental risk factors and childhood leukemia: history of paint exposure OR(5.75), 95%CI(3.17,10.44);Toxic chemical exposure history OR(3.46), 95%CI(2.00, 6.00); Family genetic history OR(3.32), 95%CI(2.52, 4.38). The OR and 95%CI of the first three factors with a correlation between environmental risk factors of mothers before pregnancy or during pregnancy and the incidence of childhood leukemia: house decoration or new furniture OR(3.19), 95%CI(1.63, 6.27); Toxic chemical exposure history OR(2.44), 95%CI(1.81,3.30); abortion history OR(2.15), 95%CI(1.28,3.61). The environmental risk factors of fathers association with childhood leukemia were: smoking history OR(2.18), 95%CI(1.19, 4.01); history of toxic chemical exposure OR(1.52), 95%CI(1.25,1.85). 
Conclusion  The incidence of childhood leukemia is closely related to the children themselves, the mother and the father. Improving the family living environment and creating a good family atmosphere provide effective measures for the prevention of childhood leukemia.

Key words: leukemia, child, Meta analysis