In so far as a disposable diaper (10) is concerned, a leg stretching unit (75) which stretches in a product longitudinal direction is disposed at an inside of a product widthwise direction than a pair of leg opening units. An area between a backside leg opening unit (35R) and a straight line which passes through a center in the product widthwise direction and which is in parallel to the product longitudinal direction is larger than an area between a foreside leg opening unit (35F) and a straight line which passes through a center of the product longitudinal direction of the leg opening unit and which extends in the product longitudinal direction. A buttocks part stretching unit (77) which is disposed so as to run across a crotch region and the back waistline region and which stretches in the product longitudinal direction is disposed at an outside of the product widthwise direction than the leg stretching unit. A front end of the buttocks part stretching unit is positioned more backward than a center of the product longitudinal direction of the leg opening unit.
