Objective. Idiopathic scoliosis is the most common pediatric spinal deformity affecting 1% to 3% of the population, and adolescent idiopathic scoliosis (AIS) accounts for approximately 80% of these cases; however, the etiology and pathogenesis of AIS are still uncertain. The current study aims to identify the relationship between calmodulin 1 (CALM1) gene and AIS predisposition, to identify the relationship between the genotypes of the SNPs and the clinical phenotypes of AIS. Methods. 146 AIS patients and 146 healthy controls were enrolled into this case-control study. 12 single nucleotide polymorphisms (SNPs) candidates in CALM1 gene were selected to determine the relationship between CALM1 gene and AIS predisposition. Case-only study was performed to determine the effects of these variants on the severity of the condition. Results. Three SNPs from 12 candidates were found to be associated with AIS predisposition. The ORs were observed as 0.549 (95% CI 0.3519–0.8579, P=0.0079), 0.549 (95% CI 0.3519–0.8579, P=0.0079), and 1.6139 (95% CI 1.0576–2.4634, P=0.0257) for rs2300496, rs2300500, and rs3231718, respectively. There was no statistical difference between main curve, severity, and genotype distributions of all of 12 SNPs. Conclusion. Genetic variants of CALM1 gene are associated with AIS susceptibility.