To provide a pants-type disposable diaper fitting in a body shape of a user and its manufacturing method capable of covering the backside of the user without the side drop while the material waste is prevented in the manufacturing process.

A longitudinal sheet 51 forming the exterior members having body-worn function for covering the body of a user is divided on an anteroposterior dividing line 52 which repeats in the longitudinal direction with the half length of the required size for forming the waist perimeter as one circle in order to divide in half in the width direction, a first split dividing line 53 formed in each one circle at the predetermined position of the first split 61, and a second split dividing line 54 formed in each one circle at the predetermined position of the second split 62, and it results that a first exterior member 63 forming the anterior body and the crotch part, and a second exterior member 64 forming the posterior body and the crotch part different from the crotch part of the first exterior member are formed, and brought together to obtain the pants-type disposable diaper 1.