To evaluate the frequencies of HLA class I (A, B) and class II (DRB1) alleles in acute myeloblastic leukemia (AML) and to compare them with the frequencies of those alleles in unrelated, healthy ethnic Turkish control subjects.We investigated the relationship of HLA alleles in 129 ethnic Turkish patients with AML and 126 unrelated, healthy, ethnic Turkish controls using the polymerase chain reaction with sequence-specific oligonucleotide probes (PCR-SSOP) method via Luminex technology.Allele frequencies of HLA-A*23, HLA-A*68, HLA-B*13, HLA-B*40, and HLA-DRB1*01 were lower in patients with AML compared with control individuals (P =.04, P =.02, P =.005, P = 02, and P =.02, respectively). In contrast, the HLA-DRB1*15 allele frequency was higher than in the controls (P =.01). The most commonly observed haplotype was A*01/B*08/DRB1*03 (5.4% vs 0.8%; P =.03) in patients with AML. In contrast, the most commonly observed haplotype was A*02/B*35/DRB1*04 (2.3% vs 3.2%) in controls. We could not find any haplotypes negatively associated with AML. Also, the homozygosity of HLA-A*01 and HLA-A*02 alleles were higher in patients with AML compared with controls (P =.046; P =.001, respectively).The HLA-DRB1*15 allele, the A*01/B*08/DRB1*03 haplotypes, and the homozygosity of HLA-A*01 and HLA-A*02 may play a presumptive predisposing factor in AML. Also, the HLA-A*23, HLA-A*68, HLA-B*13, HLA-B*40, and HLA-DRB1*01 alleles have been found to be negatively associated with AML.