Background: Hepatocellular carcinoma is one of the leading causes of death for chronic liver disease Objective: To evaluate therapeutic efficacy and the safety of Cooltip radiofrequency ablation (RFA) with single electrode to treat hepatocellular carcinomas (HCC) of less than 5 cm in maximum diameter Materials and Methods: In this prospective study, 30 patients with HCCs (2.49 cm; range, 0.8 - 4.88 cm) were enrolled.