PROBLEM TO BE SOLVED: To provide an underpants type wearing article allowing good replacement of a diaper by avoiding a lateral tear when breaking a side seam part.SOLUTION: The underpants type wearing article 10 includes a waistline opening part 11 and a pair of opening parts 12 around legs. The underpants type wearing article includes a pair of right and left side seam parts 3 wherein a member constituting the abdominal side and a member constituting the back side are overlapped in a palm jointing state. An inner sheet member 2 covering a waistline or the periphery of an abdomen of a wearer is joined to the skin surface side of the abdominal side member and/or the back side member. A waistline belt-like non-adhesion belt 21 not bonded to the abdominal side member and/or the back side member is present in a lower end part area in a height direction of the wearer of the inner sheet member, and the inner sheet member having the belt-like non-adhesion belt is joined in the side seam parts. The underpants type wearing article has a breakage guidance structure 23 for guiding the breakage in the height direction in at least one of right and left near the side seam parts.COPYRIGHT: (C)2012,JPO&INPIT【課題】サイドシーム部の破断の際に横裂きを回避して良好なおむつの取り換えを可能とするパンツ型着用物品を提供する。【解決手段】胴回り開口部11と一対の足回り開口部12とを有するパンツ型着用物品10であって、前記パンツ型着用物品には、その腹側を構成する部材と背側を構成する部材とが合掌状態に重ね合わされた左右一対のサイドシーム部3があり、かつ、前記腹側部材及び/又は背側部材の肌面側には着用者の胴回りまたは腹回りを覆う内側シート部材2が接合されており、前記内側シート部材の着用者の身丈方向の下端部領域に前記腹側部材及び/又は背側部材と非接着とされた胴回り帯状非接着帯21があり、該帯状非接着帯を有する内側シート部材が前記サイドシーム部において接合されており、前記帯状非接着帯は、そのサイドシーム部の近傍の左右の少なくとも一方において身丈方向の破断を誘導する破断誘導構造23を有するパンツ型着用物品。【選択図】図1