A calibration assist apparatus is an apparatus for use in a curving system (1), the curving system including an elongated flexible portion (21) and a curve detection unit (22) which is provided in the flexible portion and which is configured to detect a curving amount of the flexible portion. The calibration assist apparatus assists in calibrating the curve detection unit. The calibration assist apparatus includes a calibrator (30) configured to restrain a deformation and a movement of the flexible portion in both directions along a first axis perpendicular to a longitudinal axis of the flexible portion and restrain a deformation and a movement of the flexible portion in at least one direction along a second axis perpendicular to the longitudinal axis and the first axis.
