The introduction device includes an operation portion 32 having a first surface 46 and a second surface 47 which is adjacent to the first surface 46 and is positioned on the thumb side of the hand to be grasped, a second direction, A curved portion 32 which can be bent in a second direction intersecting the first axis portion 61 and a first shaft portion 61 projecting from the first surface 46 in a direction intersecting the longitudinal axis 36 of the operating portion 32, A first rotating body 51 that is operated to bend in the first direction and a second shaft part 63 that extends in the direction along the first shaft part 61 at a position closer to the thumb than the first shaft part 61 are centered And a second rotating body 52 provided on the second face 47 side within the operation range 56 of the thumb and operated when the bending portion 32 is bent in the second direction.導入装置は、第1面46と、第1面46と隣接するとともに把持する手の親指側に位置される第2面47と、を有する操作部32と、第1方向と前記第1方向と交差する第2方向とに湾曲可能な湾曲部32と、操作部32の長手軸36と交差する方向に第1面46から突出する第1軸部61を中心に回転可能で、湾曲部32を前記第1方向に湾曲させる際に操作される第1回転体51と、第1軸部61よりも前記親指に近い位置で第1軸部61に沿った方向に延びる第2軸部63を中心に回転可能で、前記親指の操作範囲56内で第2面47側に設けられ、湾曲部32を前記第2方向に湾曲させる際に操作される第2回転体52と、を備える。
