The endoscopic system includes an endoscope having an insertion portion which is inserted into a body and has a forceps insertion duct, and a light emitting member which has an end portion that emits the light and is inserted into a hollow organ in the body through the forceps insertion duct of the endoscope. The light emitting member issues positional information of the hollow organ which is detected through the endoscope orally and gastrically inserted into an abdominal cavity by causing the end portion to emit the light in the hollow organ. The system includes a treatment instrument by which a treatment is conducted in the abdominal cavity in cooperation with the endoscope.