A flexible tube insertion apparatus includes a flexible tube having flexibility and configured to be inserted into an object to be inserted, one or more external force detectors disposed on the flexible tube and configured to detect a force of an external force applied to the flexible tube when the flexible tube is twisted in at least one direction, and a providing device configured to provide twisting information regarding a twisting direction of the flexible tube for releasing a loop section formed in the flexible tube, according to a direction in which the flexible tube is twisted and the detected force of the external force.
