To provide a bobbin case body which prevents a yarn of a cheese- wound yarn pack body from being carelessly untwisted, and is excellent in convenience.

A pair of flange members 2, 3 are disposed on both ends in the axial direction of the bobbin case body 1 with the yarn 12 cheese-wound in a multi-layer around an outer circumference of a cylindrical core 11. Holding shafts 21, 31 are extended in the axial direction from inner circumferences of the flange members 2, 3, the holding shafts 21, 31 are passed through the inner circumference of the core 11, and tips are coupled with each other by welding WD, etc. A spacer 4 is interposed between the bobbin case body 1 and end faces facing each other of the flange members 2, 3, and projecting edges 24, 33 to surround outer circumferences of both ends in the axial direction of the bobbin case body 1 are provided in a circumferential direction.