An adjustable brassiere includes a pair of cup parts, a base part supporting the cup parts, a back part, and straps. Each cup part has, on its back surface, an underbust adjustment pocket and a volume adjustment pocket. The base part is continuous with the cup parts and has a stretchable skin-side base part and a front-side base part that are layered. The front-side base part includes a wire insertion part that has substantially the same curve as a curve of a lower edge of the cup part on a front surface. The skin-side base part and the front-side base part are fixed to each other at the front center tops, side edges, and a lower end, and the cup lower edge of the skin-side base part and the wire insertion part of the front-side base part are not fixed to each other, except for both ends thereof.