Turkey remains an intermediate area for prevalence of hepatitis B virus (HBV) surface antigenemia. The sheepraising areas of Turkey also pose a high risk for cystic hydatid disease (CHD). Both HBV infection and CHD are major public health issues particularly in eastern parts of Turkey; however, there is no data regarding HBV infection in patients who have had CHD. The aims of this study were to evaluate the association between HBV infection and CHD and suggest ways to reduce HBV infection which is still widespread in Turkey. A retrospective study was conducted with 94 adult patients with active CHD referred to the hepatology department, Yuzuncuyil University School of Medicine from December 2010 to December 2012. All subjects came from rural areas of the region and underwent ultrasonography of abdomen which detected CHD of the liver. All the patients were serologically positive for Echinococcus granulosus. The control group consisted of 500 patients (300 men and 200 women) referred to the internal medicine clinics for other reasons. The patients with CHD and in the control group were tested for the existence of HBs antigen according to the standard procedures. The seroprevalence of HBs antigen was significantly higher in patients with active CHD than those in the control group (12.7% vs 5.2%; P=0.0017). Our data indicate that there is significant association between HBV infection and CHD. All patients with CHD should be screened for HBV infection.