To provide an arch support orthosis which holds the heel side arch of the foot of a wearer, and effectively holds the cuboid bone and navicular bone portions by the entire orthosis.SOLUTION: An arch support orthosis 1 comprises； a firmly tightening band 12 adjustable in length, having elasticity and wound around the foot so as to go around the sole from the instep portion just before the ankle of the foot of a person； and a support member 13 having a specific shape and a soft quality of material. The support member 13 is attached to an inner surface side of a prescribed part which is placed at the sole surface side of the firmly tightening band 12. The support member 13 which is bent to be recessed forward in the width center so as to have a rear end edge part 131 corresponded to the curve of the sole surface front side of the heel of the person is such that: a longitudinal width of a part corresponding to the sole inside of the person is made wide； a longitudinal width of a part 133 corresponding to a sole outside is made narrower than a longitudinal width of the part 132 corresponding to the sole inside； and the shape has a prescribed thickness T.SELECTED DRAWING: Figure 2【課題】装着者の足の踵側のアーチを保持し、装具全体で立方骨、舟状骨の部分を効果的に保持できるようにしたアーチサポート装具を提供する。【解決手段】アーチサポート装具１であって、人の足の足首直前の甲の部位から足裏を回って一周するように足に巻き付ける長さ調整可能かつ伸縮性を持つ堅締用バンド１２と、特定の形状で、柔軟な材質のサポート部材１３とを備え、堅締用バンド１２の足裏面側に来る所定の箇所の内面側にサポート部材１３を取り付け、サポート部材１３はその後端縁部１３１が人の踵の足裏面前側の曲線に対応するように、横幅中央部で前方に凹となるように湾曲し、かつ、人の足裏内側に対応する部分の前後幅を幅広にし、足裏外側に対応する部分１３３の前後幅を足裏内側に対応する部分１３２の前後幅よりも幅狭とし、かつ所定の厚みＴを持つ形状にしたものである。【選択図】図２
