Abstract: A ventilation device is provided in a shoe. The device includes a porous member fitted in a receiving means in a rear of the insole, an intake pipe interconnected between a first check valve and the porous member, and a discharge pipe interconnected between a second check valve and porous member. Foul air is driven from porous member to the outside through the intake pipe and second check valve when the porous member is compressed by a foot. Conversely, fresh air is drawn into the porous member from the outside through the first check valve and intake pipe when the porous member is returned from the compressed state to an original state as the foot stops exerting force thereon.