A foldable bottle includes a bottle body, which has a first annular wall extending in a top-bottom direction, a top connection wall extending upwardly from the first annular wall, a second annular wall extending downwardly from the first annular wall, a third annular wall extending downwardly and foldably from the second annular wall, and a bottom wall connected to the third annular wall. The bottle body is changeable between an unfolded state, where the second annular wall and the third annular wall are unfolded to extend outwardly and downwardly from the first annular wall, and a folded state, where the second annular wall and the third annular wall are folded and inserted into the first annular wall.
