Abstract: A disposable adult diaper comprising a waterproof backing sheet, an absorbent pad assembly, and a non-woven hydrophobic top sheet. The top sheet overlies the absorbent pad assembly and is folded about the backing sheet with end margins overlapping. On the overlapped portion of the top sheet there is provided pressure-sensitive adhesive for removably attaching the diaper to an undergarment of the wearer. The diaper is folded into a box-pleated configuration for better fluid tightness and fluid capacity. The absorbent pad assembly may be made with or without top or bottom wadding sheets and the most preferable embodiment utilizes a bottom wadding sheet integrated to the wood fluff of the absorbent pad by a water spray.