To provide a cover for keeping an underwear from getting dirty due to touching to a toilet ball or the floor of a toilet room, or because of becoming dirty with urine itself by wrapping the underwear put down to his (her) feet or knees.

This cover is made through the following steps: cutting off both ends of a waterproof fabric 1 so as to be formed into a symmetric arched shape, attaching stretchable rubbers (2) and (2') respectively to the cut portions of the fabric, attaching detachable members (3), (3'), (4), and (4') to the both ends of the remaining other two sides of the fabric, and attaching detachable members (5) and (5') to the middle between the remaining other two sides of the fabric.