Objective To study the association of MIF-173 locus polymorphism and the risk of prostate cancer (PCa) in China. Methods A case control study including 259 PCa patients and 301 age-matched controls was conducted. The polymorphisms of MIF-173 locus were analyzed by poly-merase chain reaction restriction fragment length polymorphism (PCR-RFLP) technique using genomic DNA isolated from peripheral blood lymphocytes. The correlations between the susceptibility to PCa and different genotypes were compared. The effect of age, smoking method and family history of canc-er were also analyzed. Results The rate of the MIF-173 * C variant allele of the PCa patients(n=259) was significantly higher than that of the controls (n=301) (36.0% vs 15.0%). The MIF-173 *C variant allele could significantly increase the risk of PCa (OR=2.96,95%CI: 1.92-4.57). Peo-ple with older age (age>70) or family history of cancer, who carried MIF-173 * C allele demonstra-ted a significantly increased risk in comparison with those carrying wild genotype of G/G(OR=3.66, 95%CI=2.02-6.62;OR=3.26, 95%CI=1.24-8.55). Conclusion These results suggested that polymorphisms of MIF-173 locus appear to influence the risk of PCa and may have synergistic effect with age and family history of cancer.