A robot main body including a hollow flexible shaft having flexibility, a hollow bending joint including a proximal end continuous with a distal end of the flexible shaft, the bending joint being bendable in a direction perpendicular to an axis of the bending joint, a wrist joint continuous with a distal end of the bending joint and rotatable around an axis of the wrist joint, an end effector attached to the wrist joint, a hollow torque transmission tube having flexibility, inserted through the flexible shaft and the bending joint, and including a distal end attached to the wrist joint, and a bending joint operating cable inserted through the flexible shaft and including a distal end attached to the bending joint, the bending joint being configured to perform a bending operation by operating the bending joint operating cable in an extending direction of the bending joint operating cable.