An electrosurgery is a fundamental operation that utilizes Joule heat generated by the passage of a radiofrequency current. Surgical simulators are demanded for training of the electrosurgical skill with fewer complications. However, foregoing simulators have never implemented a series of physics phenomena in electrosurgery. The aim of this study is to construct a surgical simulator with a unified physics-based modeling of whole processes of electrosurgery. In this paper, we developed an electrosurgical cutting simulation system with consideration of a series of physical phases: electrical, thermal, and structural phases. Especially, the structural change based on the vaporization and mechanical rupture is modeled. The experiments using porcine livers compared the simulated temperature change with the measured one in electrosurgical cutting, and the effectiveness of the proposed model was found. In addition, the rate-controlling step for real-time electrosurgery simulation was examined.