A liquid storage body having a bag formed of two layers of flexible sheets (13A, 13B) and a hollow plug connected to the bag, the liquid storage body comprising: a first end portion which is an end portion of the bag in an axial direction of the plug, the first end portion being connected to the plug; a second end portion which is an end portion of the bag in the axial direction, the second end portion being provided on an opposite side from the first end portion; a pair of edge portions (135, 136) each of which is provided on each end portion of the bag in an orthogonal direction, the orthogonal direction being a direction that is parallel to a sheet surface of the bag in which liquid is not stored and is orthogonal to an extending direction, the extending direction being a direction from the first end portion to a second end portion of the bag, wherein at the pair of edge portions (135,136), the two layers of the sheets (13A,13B) are bonded to each other; a liquid storage portion having an enclosed space in which liquid can be stored, the liquid storage portion being connected to the plug at the first end portion; and an extension portion which is a portion that does not store the liquid and which is connected to an extending direction side of the liquid storage portion, the extension portion having a length in the extending direction longer than a length in the orthogonal direction of the edge portion; an open portion (143, 144, 145) formed between the two layers of the sheets provided on an end on an extending direction side of the extension portion; wherein the extension portion includes a plurality of first connected portions (140, 141), which are portions at which the two layers of the sheets are bonded to each other and which extend in the extending direction characterised in that an interval in the orthogonal direction between adjacent two of the first connected portions is smaller than a length in the extending direction of the extension portion. a first end portion which is an end portion of the bag in an axial direction of the plug, the first end portion being connected to the plug; a second end portion which is an end portion of the bag in the axial direction, the second end portion being provided on an opposite side from the first end portion; a pair of edge portions (135, 136) each of which is provided on each end portion of the bag in an orthogonal direction, the orthogonal direction being a direction that is parallel to a sheet surface of the bag in which liquid is not stored and is orthogonal to an extending direction, the extending direction being a direction from the first end portion to a second end portion of the bag, wherein at the pair of edge portions (135,136), the two layers of the sheets (13A,13B) are bonded to each other; a liquid storage portion having an enclosed space in which liquid can be stored, the liquid storage portion being connected to the plug at the first end portion; and an extension portion which is a portion that does not store the liquid and which is connected to an extending direction side of the liquid storage portion, the extension portion having a length in the extending direction longer than a length in the orthogonal direction of the edge portion; an open portion (143, 144, 145) formed between the two layers of the sheets provided on an end on an extending direction side of the extension portion; wherein the extension portion includes a plurality of first connected portions (140, 141), which are portions at which the two layers of the sheets are bonded to each other and which extend in the extending direction characterised in that an interval in the orthogonal direction between adjacent two of the first connected portions is smaller than a length in the extending direction of the extension portion.