An covered endoscope type of endoscopic apparatus has a covered endoscope and a cover for covering the covered endoscope. The covered endoscope has an elongated flexible inserted portion, an operated portion formed on the base end side of the inserted portion, and a universal cord extending from a side portion of the operated portion. The cover is formed of an inserted portion cover member, an operated portion cover member and a cord cover which cover the inserted portion, the operated portion and the universal cord of the covered endoscope, respectively. An operated endoscope portion fixation mouth member having a forceps inlet and an expansion tube mouth to which an expansion tube provided on an expander is connected is provided at a base end of the inserted portion cover member. An air supply tube, a water supply tube and an aspiration tube are inserted through the inserted portion cover member, the operated portion cover member and the cord cover. The overall length of the aspiration tube, the air supply tube and the water supply tube of the cover is set so as to be greater than the sum of the lengths of the inserted portion, operated portion and universal cord of the covered endoscope.