To use an electrical surgical instrument in various modes to various surgical methods.

This electrical surgical instrument having characteristics and advantages different from those of a well-known structure is used by a surgeon. Before the operation is started, the surgeon presets not only an operation mode but also the other operational parameters, especially a power level. A three-button finger switch handpiece and a three-way foot switch are used to utilize two bipolar mode at the full-range power level including five operation modes, that is, three unipolar modes and a new turbo mode for curing serious bleeding part.