A pull-on disposable diaper was patented with a height direction and a transverse direction that is orthogonal to the height direction. The diaper is generally symmetric about a center line bisecting the diaper in the transverse direction. The diaper comprises a pants-like covering component with an inner surface facing a wearer’s body and an outer surface facing a wearer’s garment. The covering component is composed of a front waist region, a rear waist region and a crotch region adapted to cover a wearer’s front region, a wearer’s rear region and a wearer’s crotch region, respectively. The covering component has a waist-hole and a pair of leg-holes and has an absorbing component that is separate from the pants-like covering component and is located on the inner surface of the pants-like covering component so as to extend over the crotch region into the front and rear waist regions. The pull-on disposable diaper also features the absorbing component with a liquid-absorbent core and a liquid-pervious coversheet. The core has a generally rectangular shape and an inner and outer surface. The coversheet covers at least the inner surface of the inner and outer surfaces of the core. The absorbing component is formed in the crotch region with a first folding guide extending from a middle zone between transversely opposite side edges that extend, in turn, parallel to each other in the height direction respective to the side edges so as to veer toward the front waist region. A second folding guide extends respective to the side edges so as to veer toward the rear waist region and a third folding guide extending in a transverse direction between the first and second folding guides. The absorbing component is folded on both sides of the center line along the third folding guide so that the core has its outer surface sections facing each other and along the first and second folding guides so that the core has its inner surface sections facing each other. The crotch region is located on the outer surface of the absorbing component with flaps extending outward of the absorbing component in the transverse direction and defining peripheral edges of the leg-holes. The flaps are elastically stretchable in a circumferential direction of the leg-holes. The outer surface of the absorbing component is separated from the flaps at least along the side edges. The vicinities of the side edges and zones separated from the flaps are covered with the coversheet.