Gelatin gel is used as a biomaterial, however, it is soft, so machining marks are generated by touching a cutter in machining, so microfabrication cannot be applied. Therefore, the authors realized machining in micro order using electric discharge machining. It is known that machining resolution is high by processing at low voltage immediately after the start of electric discharge machining. However, at low voltage, the processing speed is slow and it is necessary to process with high voltage in order to improve the processing efficiency. In this research, we investigated the processing characteristics when applying high voltage. As a result, until the voltage reaches a certain level, the processing width of the groove becomes thicker as the voltage is increased, but when even higher voltage is applied, the processed width of the groove does not change, and a change such as a melted mark of gelatin remaining in the groove appeared.