In a manufacturing apparatus of an absorbent product, extended elastic yarns to be a first middle elastic member and extended elastic yarns to be leg elastic members are bonded between a first sheet and a second sheet and arranged crossing each other in manufacturing an outer covering sheet. A first middle elastic member and an inclined part of the leg elastic members crossing the first middle elastic member are simultaneously and reliably cut in a crossing area of the both elastic members by first cutting blades tilted relatively to a direction where the first middle elastic member is positioned and second cutting blades tilted relatively to a direction where the inclined part is positioned. Thus, it is possible to easily form the outer covering sheet which maintains elasticity in a required portion and has high flexibility.