To keep sufficient tightening force while adhering to the foot of a wearing person for avoiding falling out by simply and easily adjusting the wearing port at the slipper or sandal whose upper is easy to wear but easily falls out.

Both of the ends of the short diameter of the insole of a slipper bottom or both of the ends of the short diameter of the insole of a sandal base are mounted by forming put-through holes 3 for putting one or several cords 4 through at several to dozens of of places on both of the sides of the the short diameter of the insole of the slipper bottom or both of the sides of the short diameter of the insole of the sandal base. The one or several cords 4 are respectively put through the the holes 3. Both of the ends of the cord 4 put through from one end to the other of the hole 3 are bound to be combined to make a cord in the state of a looped ring. In another manner, the cord 4 put through from one end to the other of the hole 3 is also put through an adjacent hole 3, and both of the ends of the cord 4 are bound to be to be combined to make a cord 4 in the state of a looped ring. A strap 5 is put through a gap made between the hole 3 and the adjacent hole 3 which the cord 4 is put through, and both of the ends of the strap 5 are bound to be combined.