The aim of this study was to investigate the prevalence of hepatitis B and hepatitis C virus infections in type 2 diabetic patients in Gaziantep, Turkey. Six hundred and ninety-two type 2 diabetic patients and 1014 healthy blood donors were included in the study. No significant difference was found between type 2 diabetic patients and the control group for seropositivity of HBsAg (5.3% vs 5.1%, p>0.05). In contrast, anti-HCV was significantly more frequent in type 2 diabetic patients (7.5% vs 0.1%, p>0.0001). We found no significant difference for HBsAg seropositivity between type 2 diabetic patients with a disease duration of 12 months or less, but anti-HCV seropositivity was significantly more frequent in diabetic patients with a longer disease duration (p<0.05). We suggest that HCV infection is not a trigger factor for type 2 diabetes mellitus but is frequently associated with it.