Hepatitis B virus (HBV) that causes Hepatitis B with a high chronic rate, could lead to hepatic cirrhosis and hepatocellular carcinoma. The IL28B gene belongs to a new interferon family λ and its genetic polymorphisms are identified to be associated with treatment effect and viral clearance. The purpose of this review is to discuss the role of the IL28B gene in treatment response and viral clearance of HBV-infected individuals, and further to reveal the mechanisms. This review could provide a theoretical basis for personalized medicines of HBV patients.