Abstract: This invention relates to a stairway platform device which is used upon a stairway to provide a stable base to assist an individual in reaching the highest portions of a wall during painting and/or wallpapering activities. The stairway platform device generally includes a platform, a front support wall which may include a retractable tuck-under leg, a rear support wall which may include a handle and/or a storage compartment, and a pair of side support walls; each side support wall including a plurality of step engagement edges and riser engagement edges. The side support walls, front support wall, and rear support wall preferably depend and are flared outwardly from the platform. Each of the side support walls, front support wall, and rear support wall may additionally include flanges which may be utilized to assist in the stacking and storage of a plurality of stairway platform devices during periods of non-use.