PROBLEM TO BE SOLVED: To provide a bag body with a fitting tool which facilitates the opening work of an opening portion sealed by the fitting tool.SOLUTION: A bag body 1 with a fitting tool has a bag main body 10 in a sealed state which has a first plane surface portion 11 and a second plane surface portion 12, and a fitting tool 20 attached to an inner surface of the bag main body 10. A first base material 21 and a second base material 22 of the fitting tool 20 are respectively attached to an inner surface of the first plane surface portion and an inner surface of the second plane surface portion 12. Width from a second fitting portion of the second base material 22 to a first side edge 22a is longer than width from a first fitting portion of the first base material 21 to a first side edge 21a. A notch 17 is formed on an upper side than the first side edge 21a of the first base material 21 at a side end portion 14 of the bag main body 10. A plurality of cutting auxiliary lines 18 is formed so as to turn to