Portable above-ground pool

An above-ground pool includes a pool bottom and a pool wall, together defining a water storage space. The pool bottom includes a lower bottom sheet connected to the pool wall and an upper bottom sheet, the upper and lower bottom sheets connected in a ring region and defining a sandwich region. A porous elastic material is disposed between the upper bottom sheet and the lower bottom sheet in the sandwich region. A water drainage device includes a water drainage valve and a water drainage pipe, and the water drainage valve penetrates through the pool bottom and connects to the water drainage pipe beneath the pool bottom. A vent hole through the lower bottom sheet, and located in a region where the pool bottom is lifted by the water drainage pipe, provides communication between the porous elastic material and an exterior of the pool.