Some studies report an increased risk of autoimmune thyroid disease in hepatitis C and B as well as in interferon therapy. Recently a new link between HCV and papillary thyroid cancer has been published. The mechanism responsible for the oncogenetic role of HCV is not well understood, but it involves immunity system and autoimmunity disorders. We designed a case-control study on HCV exposure. To assess the positivity to HCV ELISA test and polymerize chain reaction technique (PCR) were used. For statistical analysis an odds ratio and corresponding 95% confidence intervals were computed using unconditional multiple-logistic-regression models. Our findings show a statistically significant association between HCV and papillary thyroid cancer (OR = 3.3, 95% CI 1.5-7.4, p=0.003), overall in female gender (OR = 3.3, 95% CI 1.2-8.7, p=0.01) and in the > or =50 years age category the risk for thyroid cancer was confirmed by the OR = 3.2 (95% CI 1.3-7.9, p=0.01). Based on our study there is an association between HCV and thyroid cancer and it is more readily detectable in countries with a high prevalence of HCV.