An endoscope system including an endoscope insertion part to be inserted into a body cavity via a trocar stabbed in a body wall, the endoscope system comprising:a detecting device detecting whether a tip of the endoscope insertion part has been drawn inside the trocar anda trocar cleaning device cleaning the inside of the trocar by supplying a predetermined fluid into the trocar when it is detected by the detecting device that the tip of the endoscope insertion part has been drawn inside the trocar.
