A folding stepstool which can be folded into a shape which enables the folding stepstool to be carried easily. In a folding stepstool, a front leg and a rear leg can be housed in a recess-shaped first space in the lower surface of a first top board, and a front leg and a rear leg can be housed in a recess-shaped second space in the lower surface of a second top board. Further, when the top plates are closed, the two front legs and the two rear legs can be housed in the internal spaces in the top plates in a closed state.