An endoscope device comprises: an endoscope including an insertion portion and a first balloon attached to a distal end of the insertion portion; and an insertion guide that is to be covered on the insertion portion to guide insertion of the insertion portion, the insertion guide comprising a second balloon on its distal end, wherein the insertion portion or the insertion guide is fixed in a body cavity by expanding the first balloon or the second balloon, respectively, wherein the first balloon and the second balloon are substantially equal to each other in friction resistance against the body cavity when they are expanded.