Abstract: Objective To investigate the association between thymic lymphom a induced by ionizing radiation and the polymorphism of Ikaros and p16 genes in mice.Methods Genomic DNA of thymic lymphoma cells was extracted by genomic DNA purification kit.PCR-restriction fragment length polym orphism(RFLP)was used to examine the single nucleotide polymorphisms(SNPs)of rs28185870(C/T)and rs28185923(C/T)of Ikaros gene and rs3695947(A/G)of p16 gene.Results The genotype of rs28185870 site in C57BL/6J and BALB/c was T/T and C/C.The genotype of rs28185923 site was C/C and T/T.The genotype of rs3695947 site was A/A and G/G.Conclusion The genotypes of rs28185870,rs28185923 and rs3695947 in C57BL/6J and BAL B/c mice with different radiosusceptibility were different.It is suggested that there is an association between the polymorphism of Ikaros andp16 genes and thymic lymphom a induced by ionizing radiation.