An endoscopic gaseous material feed system comprises an endoscope 1 having a solid-state image sensor device 81 incorporated into a fore distal end portion of an elongated endoscopic insertion rod to be introduced into a body cavity of a patient or examinee, a gas feeder 3 loaded with a gas tank 60 which is packed with carbon dioxide gas to be sent to the body cavity, a light source 2 incorporating an air pump to supply air to the body cavity, a processor 4 for generating video signal data of an endoscopically captured picture image on the basis of electric signals from the solid-state image sensor 81, a detector 87 provided in the processor 4 and adapted to detect whether or not the endoscope is currently placed in a body cavity, from video signal data of the processor, and a feed gas source controller 85 provided in the processor and adapted to permit a supply of carbon dioxide gas or air when the detector 87 makes an affirmative judgment that the endoscope 1 is currently placed in a body cavity and to prohibit a supply of carbon dioxide gas when the detector 87 makes a negative judgment.
