A three-pronged box flap closure device is provided for securing together three box flaps of a moving box or carton without the use of adhesive tape or overlapping the box flaps to secure the same together. One or more closure devices are contemplated for each box end, wherein each closure device comprises a first and second upper prong member forming a substantial V-shape with a common apex. A third prong member extends from the apex and between the first and second prong members, wherein the third prong member is disposed below the plane created by the first and second prong members. The first and second prong members are adapted to be positioned over a pair of aligned box flaps, while the lower prong member extends beneath a third, undermost box flap below the aligned box flaps, thereby sandwiching the three box flaps together along one side of the box end.