To improve the water resistance and the smoothness of the appearance, to simplify the assembly work to provide a quality stable insertion device. Insertion device includes an insertion portion main body 41 extending linearly, the sheathing tube 43 for covering the outer periphery of the insertion portion main body 41, with respect to an imaginary circle 46 on the sheathing tube 43 around the central axis C of the insertion portion main body 41 provided on the outer periphery of the outer cover tube 43 in a meandering on, provided to contract in a direction along the imaginary circle 46, an annular band member 44 for fixing the outer skin tube 43 into the insertion portion main body 41, a.外観の平滑性と防水性を向上し、組み立て作業を簡略化し品質的に安定した挿入装置を提供する。 挿入装置は、線状に延びる挿入部本体41と、挿入部本体41の外周を被覆する外皮チューブ43と、挿入部本体41の中心軸Cを中心とする外皮チューブ43上の仮想円46に対して蛇行して外皮チューブ43の外周に設けられ、仮想円46に沿う方向に収縮して、外皮チューブ43を挿入部本体41に固定する環状のバンド部材44と、を備える。
