The ataxia telangiectasia mutated (ATM) gene plays a major role in repairing the double-strand breaks and maintaining the genome stability. In this case-control study, associations of seven ATM single-nucleotide polymorphisms (rs600931, rs189037, rs652311, rs624366, rs228589, rs227092 and rs227060) with risks in childhood leukemia in a Taiwanese population were investigated. Two hundred and sixty-six patients with childhood leukemia and 266 age-matched healthy controls recruited were genotyped and analyzed. The P-values of the distributions of the genotypic frequencies in the seven ATM polymorphisms were 0.8925, 0.2835, 0.5772, 0.8731, 0.3641, 0.9181 and 0.5071, respectively. The Pvalues of the distributions of the allelic frequencies in the seven ATM polymorphisms were 0.6158, 0.1179, 0.6971, 0.7944, 0.1887, 0.6605 and 0.2747, respectively. Although the results did not indicate that ATM polymorphism is directly associated with childhood leukemia, the gene-gene and gene-environment interactions of ATM with other factors is worthy of further investigation in the future.