Radiofrequency ablation (RFA) is one of minimal invasive treatment methods and it has been showing comparable overall survival with surgery in early or small hepatocellular carcinomas (HCCs) and better cost-effectiveness. However, it is suffering from high local tumor progression (LTP) rate. To reduce LTP rate, creation of large ablative zone has been attempted in various strategies. A separable cluster electrode is a new type of RFA electrode. It consists of three individual applicators and the applicators can be incorporated as a single handle such as a cluster electrode, and can be separated as three electrodes, depending on operators' needs. It allows high flexibility to operators and the preclinical results were promising. Herein, we want to evaluate the clinical feasibility of the electrodes by observing major complication rates, technical success rate and 12-months LTP rate.