Orosomucoid 1-like 3 (ORMDL3) gene, located on chromosome 17q21, is an asthma candidate gene that encodes ORMDL3. This molecule has been reported to play a role in airway remodeling and bronchial hyper-responsiveness. In this study, we aimed to investigate the possible association of ORMDL3 single nucleotide polymorphism (SNP) (rs12603332) with susceptibility to allergic asthma in Iranian Northwestern Azeri population. 193 asthmatic patients and 185 normal individuals were included. Genomic DNA was extracted and genotyping was performed by standard restriction fragment length polymorphism-polymerase chain reaction RFLP-PCR method using BstUI restriction enzyme. Our results showed dominant presence of TC genotype and C allele in both patients (49.2% and 59.8%, respectively) and controls (48.6% and 60%, respectively). Frequency of genotypes and alleles showed no significant difference between two groups (p=0.994 and p=1.00, respectively). None of alleles could be defined as risk allele for allergic asthma (OR=0.99, 0.88-1.12, 95% CI). We failed to show significant association between ORMDL3 rs12603332 with predisposition to allergic asthma in Iranian Northwestern Azeri population. More studies with larger number of participants should be done to find more reliable results for such association.