A battery packaging body (1, 101, 201, 301) for packaging a battery, comprising: a first member (10, 110, 210); and a second member (20, 120, 220, 320) capable of accommodating the battery between the same and the first member (10, 110, 210), wherein the first member (10, 110, 210) is a plate-shaped mount, the second member (20, 120, 220, 320) is a blister cover, the first member (10, 110, 210) and the second member (20, 120, 220, 320) are fixed to each other at least at their peripheral edge parts, the second member (20, 120, 220, 320) has an accommodating projection (24, 124, 224, 254) protruding in a thickness direction of the second member (20, 120, 220, 320) so as to form an accommodating space (S, S1, S2) capable of accommodating the battery between the same and the first member (10, 110, 210), and a non-fixed part (32, 132, 232, 262) provided at a position continuous to the accommodating projection (24, 124, 224, 254) and not fixed to the first member (10, 110,210), characterized in that the second member (20, 120, 220, 320) has a first rib part (26a, 126a, 226a, 256a) provided along the accommodating projection (24, 124, 224, 254) and protruding in the thickness direction of the second member (20, 120, 220, 320), the non-fixed part (32, 132, 232, 262) is positioned on an opposite side to the first rib part (26a, 126a, 226a, 256a) across the accommodating projection (24, 124, 224, 254) and constitutes a part of a cuttable region (P, P1, P2) cut when the battery packaging body (1, 101, 201, 301) is opened, and the first rib part (26a, 126a, 226a, 256a) extends in a direction crossing a direction in which the non-fixed part (32, 132, 232, 262), the accommodating projection (24, 124, 224, 254) and the first rib part (26a, 126a, 226a, 256a) line up. a first member (10, 110, 210); and a second member (20, 120, 220, 320) capable of accommodating the battery between the same and the first member (10, 110, 210), wherein the first member (10, 110, 210) is a plate-shaped mount, the second member (20, 120, 220, 320) is a blister cover, the first member (10, 110, 210) and the second member (20, 120, 220, 320) are fixed to each other at least at their peripheral edge parts, the second member (20, 120, 220, 320) has an accommodating projection (24, 124, 224, 254) protruding in a thickness direction of the second member (20, 120, 220, 320) so as to form an accommodating space (S, S1, S2) capable of accommodating the battery between the same and the first member (10, 110, 210), and a non-fixed part (32, 132, 232, 262) provided at a position continuous to the accommodating projection (24, 124, 224, 254) and not fixed to the first member (10, 110,210), characterized in that the second member (20, 120, 220, 320) has a first rib part (26a, 126a, 226a, 256a) provided along the accommodating projection (24, 124, 224, 254) and protruding in the thickness direction of the second member (20, 120, 220, 320), the non-fixed part (32, 132, 232, 262) is positioned on an opposite side to the first rib part (26a, 126a, 226a, 256a) across the accommodating projection (24, 124, 224, 254) and constitutes a part of a cuttable region (P, P1, P2) cut when the battery packaging body (1, 101, 201, 301) is opened, and the first rib part (26a, 126a, 226a, 256a) extends in a direction crossing a direction in which the non-fixed part (32, 132, 232, 262), the accommodating projection (24, 124, 224, 254) and the first rib part (26a, 126a, 226a, 256a) line up.