A bending mechanism (81) includes a vertical driving portion (83UD) that a central axis (83c) extends along an X-axis direction, a horizontal driving portion (83LR) that a central axis (83c) extends along the X-axis direction and is adjacent to the vertical driving portion (83UD) in an Y-axis direction, a vertical rotary portion (85UD) which is coupled to the vertical driving portion (83UD) and which is rotated, and a horizontal rotary portion (85LR) which is coupled to the horizontal driving portion (83LR) and which is rotated and which is adjacent to the vertical rotary portion (85UD) in the Y-axis direction. The bending mechanism (81) further includes a holding portion (101) which holds an operation wire (300UD) and an operation (300LR) wire so that the operation wire (300UD) extends from the vertical rotary portion (85UD) to a rear surface (51d) on the side where the horizontal rotary portion (85LR) is disposed and so that the operation wire (300LR) extends from the horizontal rotary portion (85LR) to the rear surface (51d) on the side of the vertical rotary portion (85UD) and further intersects with a vertical operation wire (500UD).