A brace comprising: a first member configured to be attached to a part of a body located along a first bone part of a wearer; a second member configured to be attached to a part of a body located along a second bone part of the wearer; and a joint mechanism configured to support the first and second members (101, 200) so that the first and second members (101, 200) can rotate with respect to each other around a rotation axis, wherein the brace further comprises an insertion-fitting member (410,420) configured to be insertion-fitted into the joint mechanism in such a manner that the insertion-fitting member (410,420) can be fixed to and removed from the joint mechanism, the joint mechanism comprises: an insertion-fitting receiving part (310c,310e) integrally provided with the first member, the insertion-fitting receiving part (310c,310e) being configured to enable the insertion-fitting member (410,420) to be insertion-fitted into the joint mechanism; and a regulation part integrally provided with the second member, the regulation part being disposed around the rotation axis in the second member, and the regulation part, which rotates around the rotation axis in an integrated manner with a rotation of the second member, makes surface contact with a projecting part (411,421) of the insertion-fitting member (410,420) fixed to the insertion-fitting receiving part (310c,310e) on a trajectory of the rotation of the regulation part, so that a range of the rotation of the second member is regulated, the projecting part (411,421) extending in a circumferential direction with respect to the rotation axis, characterized in that the insertion-fitting member (410,420), which is insertion-fitted into the insertion-fitting receiving part (310c,310e), is selected from a set of a plurality of insertion-fitting members (410,420) according to a desired regulated rotation range, the plurality of insertion-fitting members (410,420) comprising projecting parts (411,421) having projecting lengths different from each other, and the joint mechanism comprises a lever (350,360) configured to press down the insertion-fitting member (410,420) in a direction toward the insertion-fitting receiving part (310c,310e) after the insertion-fitting member (410,420) is inserted into the insertion-fitting receiving part (310c,310e). a first member configured to be attached to a part of a body located along a first bone part of a wearer; a second member configured to be attached to a part of a body located along a second bone part of the wearer; and a joint mechanism configured to support the first and second members (101, 200) so that the first and second members (101, 200) can rotate with respect to each other around a rotation axis, wherein the brace further comprises an insertion-fitting member (410,420) configured to be insertion-fitted into the joint mechanism in such a manner that the insertion-fitting member (410,420) can be fixed to and removed from the joint mechanism, the joint mechanism comprises: an insertion-fitting receiving part (310c,310e) integrally provided with the first member, the insertion-fitting receiving part (310c,310e) being configured to enable the insertion-fitting member (410,420) to be insertion-fitted into the joint mechanism; and a regulation part integrally provided with the second member, the regulation part being disposed around the rotation axis in the second member, and an insertion-fitting receiving part (310c,310e) integrally provided with the first member, the insertion-fitting receiving part (310c,310e) being configured to enable the insertion-fitting member (410,420) to be insertion-fitted into the joint mechanism; and a regulation part integrally provided with the second member, the regulation part being disposed around the rotation axis in the second member, and the regulation part, which rotates around the rotation axis in an integrated manner with a rotation of the second member, makes surface contact with a projecting part (411,421) of the insertion-fitting member (410,420) fixed to the insertion-fitting receiving part (310c,310e) on a trajectory of the rotation of the regulation part, so that a range of the rotation of the second member is regulated, the projecting part (411,421) extending in a circumferential direction with respect to the rotation axis, characterized in that the insertion-fitting member (410,420), which is insertion-fitted into the insertion-fitting receiving part (310c,310e), is selected from a set of a plurality of insertion-fitting members (410,420) according to a desired regulated rotation range, the plurality of insertion-fitting members (410,420) comprising projecting parts (411,421) having projecting lengths different from each other, and the joint mechanism comprises a lever (350,360) configured to press down the insertion-fitting member (410,420) in a direction toward the insertion-fitting receiving part (310c,310e) after the insertion-fitting member (410,420) is inserted into the insertion-fitting receiving part (310c,310e).