Irreversible electroporation (IRE), developed and manufactured by AngioDynamics US Ltd, can ablate tumor by fenestrating the cancer cell membrane by electric pulse. The anti-tumor effect does not result from thermotherapy, so is also not diminished by adjacent vessels. Several pre-clinical studies have already demonstrated IRE is a safe and effective treatment for live cancers. The system has been approved as safe by the European Union (EU) in 2008 and received Food and Drug Administration (FDA) approval in 2010. However, there are still few experiences in using IRE for tumor ablation in Taiwan. In this study, the investigators will perform IRE for 40 inoperable patients with liver cancers adjacent to vessels who are suitable to receive radiofrequency ablation (RFA) in the investigators hospital. The investigators will evaluate the potential side effect and ablate effect of tumors by abdominal computed tomography (CT) or magnetic resonance imaging (MRI), and the investigators will also follow-up this patients for 2 years to evaluate the overall survival and local recurrence rate. The investigators will appraisal the clinical feasibility and advantage of the system by this study.