An insertion apparatus includes: an introducing duct including; insertion portion cover portion for covering an insertion portion extending from a distal side portion of a handling portion constituting an endoscope; and a spiral duct which is disposed on an inner circumferential surface side of the insertion portion cover portion, and has on a circumferential surface of the spiral duct, a propulsion power generating portion for applying a propulsion power for introducing the insertion portion into a deep portion in a body cavity, to the insertion portion covered by the insertion portion cover, and a rotating device comprising a rotating portion for rotating the spiral duct equipped to the introducing duct.