Objective: To investigate the association between the cluster of differentiation 14 (CD14)-159C/T (rs2569190) gene polymorphism and susceptibility to acute brucellosis in an Iranian population. Methods: The study included 153 Iranian patients with active brucellosis and 128 healthy individuals as the control group. Genotyping of the CD14 variant was performed using an amplification refractory mutation system-polymerase chain reaction method. Results: The prevalence of CD14-159 TT and CT genotypes were associated with increased risk of brucellosis [odds ratio (OR) = 1.993, 95% confidence interval (95% CI) = 1.07-3.71, P = 0.03 for CT; OR = 3.869, 95% CI = 1.91-7.84, P = 0.01 for TT genotype. Additionally, the minor allele (T) was significantly more frequently present in brucellosis patients than in controls (61% vs. 45%, respectively), and was a risk factor for brucellosis (OR = 3.058, 95% CI = 1.507-6.315, P = 0.01). Conclusions: The findings provided suggestive evidence of association of the CD14-159C/T gene polymorphism with susceptibility to acute brucellosis in the Iranian population.