There is provided an insufflation system and an insufflation apparatus which can prevent a pressure inside a lumen from rapidly increasing and can achieve operability matched to a sense an operator. The insufflation apparatus is connected to an endoscope and an insertion assisting tool which guides the endoscope into the gastrointestinal tract. Carbon dioxide can be insufflated into a gastrointestinal tract of a patient through an internal conduit of the endoscope according to an operator's operation (manual insufflation). When the operator instructs the insufflation apparatus to perform the automatic insufflation, carbon dioxide is intermittently insufflated into the gastrointestinal tract through the insertion assisting tool so as to make the pressure inside the gastrointestinal tract become a set pressure (automatic insufflation). The insufflation flow rate of the manual insufflation is switched between the high flow rate and the low flow rate according to ON/OFF state of the automatic insufflation.
