In a method for inserting an endoscopic device, a guide wire is punctured into a subject from outside the body. A tip portion of the wire is inserted into a first hollow organ. A tip-side portion of the inserted wire is projected into a lumen of a second hollow organ that communicates with the first via an opening, from the opening. An endoscopic device is inserted through a flexible endoscope and pushed into the second hollow organ. A tip portion of the device is locked onto the tip-side portion of the wire projecting into the second hollow organ. A portion of the wire outside the body of the subject is held and is tugged outside of the body. The tip portion of the device is thus pulled into the first hollow organ from the second, via the opening. Therefore, the endoscopic device can be led to the first hollow organ.
