To facilitate the pushing of a double pipe without using a complicated mechanism.

A double pipe bending apparatus includes a processing mechanism, a double pipe pushing mechanism having a chuck mechanism and a carriage, and an apparatus main body provided with a rail and a frame. The double pipe pushing mechanism is provided with an outer core bar 14 arranged between inside and outside pipes, an inner core bar arranged inside an inner pipe 2a, a slide rod 45 arranged at a rear end part of the inner core bar 43, a core bar shaft 47 arranged between the slide rod and the frame, a slide ring 49 which is arranged on the slide rod and contact with an end of the inner pipe, and a pushing lug 51 which is arranged on the slide rod and contact with an end of an external pipe 2b. The pushing lug is held by the chuck mechanism when pressured, moved on the apparatus main body by the carriage, and presses the ends of the inside and outside pipes toward a bending mechanism.