In Crimean-Congo Hemorrhagic Fever (CCHF), the main target of the virus is endothelial cells, monocytes and hepatocytes. The virus in these cells leads to the development of capillary vessels dysfunction, which induces clinical and pathological changes during the disease. Increase in capillary permeability and coagulation dysfunction constitute a tendency to bleed. In the current study, we aimed to investigate the relationship between VKORC1 and bleeding tendency in CCHF. Forty-eight consecutive patients with a laboratory-confirmed diagnosis of CCHF were treated with blood products, and 37 healthy volunteers as the control group were prospectively enrolled into the study. The DNA was obtained from each sample using PCR amplification method, and VKORC1 1639 G>A gene polymorphisms were scanned in the DNA samples. In CCHF group of patients with bleeding VKORC1 gene were analyzed. Normal genotype was detected in 5 (22.7%) patients, homozygote mutation was detected in 2 (9.1%) patients and heterozygote mutation was detected in 15 (68.2%) patients, respectively. Furthermore, the G allele frequency was statistically higher in study group (51 [53%] vs. 27 [36%]) (p<0.005). It seems to be that VKORC1 gene A allele frequencies saliently higher in CCHF. This might be associated with increased bleeding risk in CCHF. Analyzing of VKORC1 gene polymorphisms could help in the risk stratification of patients with CCHF.