Abstract: A shielded disk mailing envelope comprising a protective envelope made of thin material such as paper, cardboard, or plastic that is adapted to receive a floppy disk cartridge assembly. The protective envelope has substantially square rear and front walls. The front and rear walls are joined at a common bottom edge which allows the front wall to pivot about this edge. Side edge flaps are pivotally joined along the side edges of the rear wall, such that these side edge flaps can be folded inwardly toward the inner surface of the rear wall. The front wall is likewise folded inwardly toward the inner surface of the rear wall. The front wall inner surface is adhered to the outer surface of the previously folded side edge flaps, thus forming an envelope. At the top edge of the rear wall a cover flap is pivotally joined. This cover flap is folded over the opening created at the top of the envelope and acts to close the envelope creating a protective container.