An insertion method for a flexible elongate member is used to insert the flexible elongate member into a tube while causing first and second holding units to perform an opening-and-closing operation for holding and releasing the flexible elongate member. The method includes acquiring information of a distance by which the second holding unit moves with respect to the first holding unit and information of an operation type used to distinguish between insertion of the flexible elongate member into the tube, stoppage of the flexible elongate member, and extraction of the flexible elongate member from the tube; generating operation information regarding an opened/closed state of the first holding portion and an opened/closed state of the second holding portion on the basis of the distance and the operation type; and controlling the insertion, stoppage, or extraction of the flexible elongate member on the basis of the operation information.