To uniformly apply hemming to a bent flange part without damaging the outside surface of an outer panel.

A hemming apparatus 1 has a lower die 10 and an upper die 20 which is arranged vertically movably above the lower die and a work 60 which is constituted by placing an outer panel 71 above an inner panel 61 is installed between the upper die 20 and the lower die 10. The upper die 20 has a planar abutting surface 21 faced downward. The lower die 10 has a hemming blade 11 which is arranged below and opposite to the abutting surface and applies hemming to the bent flange part 73 formed in the peripheral part of the outer panel 71, and a work housing part 12 is formed inside the hemming blade 11. A pressing/positioning device 50 is provided in the upper part of the work housing part 12 and the pressing/positioning device 50 works so that the bent flange part 73 is positioned in a position between the abutting surface 21 and the top surface 11a of the hemming blade 11 and the work 60 is pressed against the abutting surface 21.