An endoscope system having: an endoscope having: an endoscope insertion section wherein the endoscope defines a channel having a distal opening in the endoscope insertion section； and a first inductance element arranged to the channel, and configured to receive a high-frequency power to generate an AC magnetic field； and a treatment tool having: a treatment tool insertion section configured to be movably inserted in the channel； an electrically powered treatment device attached to the treatment tool insertion section； and a second inductance element arranged to the treatment tool insertion section, wherein the second inductance element is electrically connected to the electrically powered treatment device, and wherein the second inductance element is inductively coupled to the first inductance element such that the AC magnetic field induces an electromotive force to generate an induced current in the second inductance element to power the electrically powered treatment device.
