An insufflation apparatus includes a gas-feeding-conduit connecting section for connecting a conduit that feeds a predetermined gas to a subject, a first conduit that connects a gas-feeding-source connecting section and the gas-feeding-conduit connecting section, a suction-conduit connecting section for connecting a conduit that sucks the predetermined gas from an inside of the subject, a pump for circulating the predetermined gas to the subject, a conduit for circulation that connects the suction-conduit connecting section and the pump, a second conduit that connects a suction-source connecting section and the conduit for circulation, and a control section that controls a switching unit to operate in a first operation mode for circulating the predetermined gas to the subject via the pump and a second operation mode for sucking the predetermined gas to the suction source side via the second conduit.