The present invention aims to improve the pants-type wearing article of prior art so that leak of body fluids otherwise occurring beyond the leg-openings can be reliably prevented even if the waist region of the wearing article slip down after the diaper has been put on the wearers body.In a disposable pants-type wearing article 1, a body fluid absorbent panel 3 provided in a crotch region extends in a longitudinal direction A and is fixed to a sheet member 11 defining inner surfaces of front and rear waist regions. The body fluid absorbent panel 3 is formed along its opposite side edges with flaps 24 and free edges 40b of the respective flaps 24 are provided with crotch region elastic members 43 attached under tension thereto. The front and rear waist regions are provided along peripheral edges of leg-openings with lower elastic members 15b attached under tension thereto. Regions of the side flaps 24 in which the free edges 40b of the flaps 24 developed in a transverse direction overlap the associated lower elastic members 15b are affixed to respective inner surfaces of the front and rear waist regions.