Patented is a pull-on disposable diaper with a height direction, a transverse direction that is orthogonal to the height direction and a back-and-forth direction. The diaper is substantially symmetric about a longitudinal center line extending in the height direction and bisecting a dimension of the diaper in the transverse direction. The diaper has an inner surface facing a wearer’s body and an outer surface facing wearer’s clothes. The diaper is composed of a front waist covering region designed to cover a wearer’s front waist region, a rear waist covering region designed to cover a wearer’s rear waist region and a crotch covering region designed to cover a wearer’s crotch region. This makes a pants-like configuration with a waist-hole and a pair of leg-holes, and is provided on the inner surface with a body fluid absorbing component extending over the crotch covering region. It further extends into the front and rear waist covering regions. The pull-on disposable diaper further comprises the body fluid absorbing component comprising a liquid-absorbent core and a liquid-pervious coversheet at least partially covering the core, having an inner surface facing the wearer’s body, an outer surface facing away from the wearer’s body and transversely opposite side edges extending parallel to each other beyond the crotch covering region into the front and rear waist covering regions and connecting the inner and outer surfaces to each other. The body fluid absorbing component is formed in the crotch covering region with a first folding guide extending from a transversely middle point between transversely opposite side edges to respective side edges in the front waist covering region, making a V-shape. A second folding guide extends from a transversely middle point between transversely opposite side edges to respective side edges in the rear waist covering region, making a V-shape. A third folding guide extends in the transverse direction between the first and second folding guides. The absorbing component is folded at least transversely opposite side edges on both sides of the longitudinal center line along the third folding guide so that the outer surfaces face each other and along the first and second folding guides so that the inner surfaces face to each other. Elastic members are provided in one of: the front waist covering region, the rear waist covering region and the crotch covering region so as to intersect the side edges in vicinities of the leg-holes. One of the elastic members provided in the front waist covering region intersects the side edges above the first crossing points at which the side edges of the absorbing component intersect the first folding guide. One of the elastic members provided in the rear waist covering region intersects the side edges above second crossing points at which the side edges of the absorbing component intersect the second folding guide. The absorbing component is folded along the first, second and third folding guides and tucked inwardly of the diaper to make up inward portions. Opposing surfaces of the inwardly tucked portions are free of direct attachment to each other, allowing the absorbing component to be unfolded along all the first, second and third folding guides. The opposing surfaces of the inwardly tucked portions are parts of the outer surface of the absorbing component. The inwardly tucked portions are free of all elastic members, which are directly bonded to at least one of: the front waist covering region and the rear waist covering region.