Aspirin-intolerant asthma (AIA) occurs from asthma exacerbation after exposure to aspirin. However, the underlying mechanisms of AIA occurrence are still unclear. The critical role of the solute carrier family 6 (neurotransmitter transporter, betaine/GABA) member 12 (SLC6A12) gene in GABAergic transmission, which is associated with mucus production in asthma, makes it a candidate gene for AIA association study. Eight single nucleotide polymorphisms (SNPs) in SLC6A12 were genotyped in 163 aspirin-intolerant asthma (AIA) and 429 aspirin-tolerant asthma (ATA) patients of Korean ethnicity. Associations between polymorphisms of SLC6A12 and AIA were analysed using multivariate logistic analysis. Results showed that two polymorphisms and a haplotype in SLC6A12, rs499368 (P= 0.005; Pcorr= 0.03), rs557881 (non-synonymous C10R, P= 0.007; Pcorr= 0.04), and SLC6A12_BL1_ht1 (P= 0.009; Pcorr= 0.05) respectively, were significantly associated with AIA after multiple testing corrections. In addition, SNPs of SLC6A12 were significantly associated with the fall rate of FEV1 by aspirin provocation suggesting that SLC6A12 could affect reversibility of lung function abnormalities in AIA patients. Although these results are preliminary and future replications are needed to confirm these findings, this study showed evidence of association between variants in SLC6A12 and AIA occurrence among asthmatics in a Korean population.