简介：Most patients (67%) had low serum levels of vitamin D. Virological response during treatment and sustained virological response (SVR) were significantly higher in group II than group I (74% versus 47%， p< 0.01). According to serum tertiles of vitamin D; there were significance increases in SVR in high tertiles compared to intermediate and low tertiles in both groups. Increases SVR were associated with high serum levels of vitamin D， male sex， younger patients， low BMI， high leucocytes count before treatment that become low during treatment， low grade of fibrosis & activity and low viremia. Logistic regression analysis confirmed that serum level of vitamin D and younger ages were the most predictor of SVR in patients with HCV under interferon therapy.