A folding bathtub includes a tub body; and a supporting ring. The supporting ring is arranged on the tub body. The supporting ring comprises a left ring part, a right ring part and an upper folding part, the left ring part and the right ring part are respectively arranged on two sides of an upper end of the tub body, and the upper folding part is arranged between the left ring part and the right ring part. The upper folding part is made of a soft material. The supporting ring achieves rotatable folding between the left ring part and the right ring part by means of deformation of the upper folding part, and the supporting ring is folded to drive the tub body to deform and be folded.