An endoscope apparatus including an insertion portion for insertion into a body cavity an image-acquisition unit disposed at a tip thereof that acquires an image of the inside of the body cavity an insertion-length measuring unit disposed at a base end of the insertion portion that measures an insertion length of the insertion portion inside the body cavity a storage unit that stores the image acquired by the image-acquisition unit in association with the insertion length measured by the insertion-length measuring unit a following decision unit that determines whether insertion movement at the tip follows insertion movement at the base end and a correcting unit that corrects the insertion length of the insertion portion associated with the acquired image to cancel a change in the insertion length measured in a non-following period on the basis of the result of that determination.
