To provide a boot keeper which keeps inside of a boot clean and prevents damage and losing shape of the boot when the boot is being stored, can be applied to the boots of all sizes and materials, is lightweight and excels in durability and needs small space for being stored when it is not used.

Porosity composition (2) is formed of plastics, such as polyolefin or polyvinyl chloride. The sheet-like porosity composition (2) is cylindrically rolled, inserted into a boot and the boot can be stored with retained shape. Moreover, when it becomes dirty, it is easily washed and sterilized.