One of the common cause of drug hypersensitivity reaction is iodinated contrast media (ICM). The hypersensitivity reaction rate in patients undergoing computed tomography examination was 1.1% in our previous study, but the usage of ICM is very popular. Currently, the mechanism of ICM induced hypersensitivity reaction is not entirely understood. This study aimed to evaluate the association between HLA-A, -B, and -C genotypes and hypersensitivity reactions (immediate and non-immediate) after contrast media exposure. Total subjects were 130 patients who underwent contrast enhanced CT studies through outpatient clinics of a tertiary referral hospital from November 2010 to August 2012. ICM-induced hypersensitivity patents (65) were matched to ICM tolerant controls at a one-to-one ratioon gender, age, and diagnosis. HLA-A, -B, -C typing were performed using PCR-sequence-based typing (SBT) method. Four kinds of ICM were used, which were iopromide, iohexol, iobitridol, and iodixanol. There were statistically significant difference in the frequencies of HLA-A*1101 (24.6% versus 10.8%, OR=2.7055, 95% CI=1.0296-7.1098, P=0.0386), HLA-B*5801 (18.5% versus 6.2%, OR=3.4528, 95% CI=1.0505-11.349, P=0.0327), and HLA-C*0602 (9.2% versus 0%, OR=0.069877, 95% CI=0.003853-1.267199, P=0.0277) between ICM-induced hypersensitivity cases and ICM-tolerant controls. The mechanism of ICM induced hypersensitivity is obscure yet, but this study showed the association, even week, with HLA-A*1101 and HLA-B*5801 as a risk biomarker, and HLA-C*0602 as a protective biomarker. Further studies are needed in large sample sizes to identify the functional mechanism of the associations.