To provide slippers with which diet, health promotion and strengthening of muscular power can be easily expected only by living a life as usual at home and in a company.

Material such as a rubber ball making it hard to balance is used for a sole part 2 of the slipper. Consequently, when trying to balance, strengthening of muscular power of particularly the waist and the lower half of the body can be expected, and furthermore improvement of blood circulation can be expected by forming the surface of the sole part in wart shape.