To provide a simplified bathtub for bedridden advanced age people/ patients, which is light-weight, can be manufactured at a low cost, the moving/ storage of which is easy, and which can be permanently installed on a bed.

Long and thin shaping bags 2, which are waterproof and extend in the lateral direction, are respectively provided in a plurality of stages on the right and left side edges and one edge on the foot side of the waterproof bottom surface 2c of this bathtub. Also, at corner sections which connect the right and left side edges and the one edge on the foot side, shaping bags 2 which extend in the vertical direction are attached. Then, in respective shaping bags 2, air bags 3a, 3b, 3c and so forth are enclosed in a manner to be removable with a chuck 2a. Then, in the air bags 3a, 3b, 3c and so forth, air is press- fed through air tubes 4a, 4b and 4c, and the air bags are expanded. Thus, the right and left side surfaces, the corner sections, and the one edge on the foot side are held high, and the bathtub is formed together with a tilted bathtub leaning surface 2d on the upper edge side.