PROBLEM TO BE SOLVED: To provide a tape type disposable diaper which is free from risks of tearing of a sheet base material constituting a fastening tape and the detachment of the fastening tape.SOLUTION: A tape type disposable diaper has a fastening tape 10 at both side end parts of a back side part B in a width direction, and the tape 10 has a sheet base material 11 and an engaging means 12 as components. The sheet base material 11 has a base part 11A and a projection part 11B. The projection part 11B is branched into an upper side projection piece 13 and a lower side projection piece 14. On both projection pieces 13, 14, an engaging means 12 capable of engaging with an abdominal side part is provided. The base part 11A has a joining region 21 which is substantially in a joined relation with the back side part B and a non-joining region 22 which is not in a joined relation substantially, and a prescribed length 11d below an upper side end edge 11x of the base part 11A is the non-joining region 22.SELECTED DRAWING: Figure 5【課題】ファスニングテープを構成するシート基材が裂けて、当該ファスニングテープが取れてしまうといったおそれのないテープタイプ使い捨ておむつを提供する。【解決手段】背側部分Ｂの幅方向両側端部にファスニングテープ１０とを有し、このテープ１０はシート基材１１及び係止手段１２を構成要素とし、シート基材１１は付根部１１Ａと突出部１１Ｂとを有し、突出部１１Ｂは上側突出片１３及び下側突出片１４に枝分かれし、両突出片１３，１４には腹側部分に係止可能な係止手段１２が備わるテープタイプ使い捨ておむつであって、付根部１１Ａは背側部分Ｂと実質的に接合関係にある接合領域２１と実質的に接合関係にない非接合領域２２とを有し、付根部１１Ａの上側端縁１１ｘから所定長１１ｄ下方までは非接合領域２２である。【選択図】図５
