Atherosclerosis (AS) is one of the leading causes of death, with variable frequencies in different populations. To this end, we examined whether AS is associated with the miR-145 rs353291 polymorphism and specific rs353291 alleles. The distribution of the rs353291 C allele and CC genotypes was significantly higher in AS patients than in controls. Compared to individuals with the rs353291 TT genotype, carriers of the rs353291 C allele showed a significant increase in the plasma levels of sCD40L, IL-6 and MCP-1 and a decrease in miR-145 expression. After ox-LDL administration, the peripheral blood mononuclear cells (PBMCs) of rs353291 C allele carriers showed significantly increased CD40 and MCP-1 expression compared with those of individuals with the rs353291 TT genotype. These data suggest that the rs353291 C allele may increase susceptibility to atherosclerosis.