PURPOSE: To provide a see-through window for a sheet which is arranged to a part of a sheet for the vinyl enclosure of a ship, a tent, a warehouse, and a house for an agricultural use so as to ensure a visual field and natural illumination and to provide an attaching method therefor.

CONSTITUTION: A see-through window for a sheet comprises a support material 2 and a press material 3 between which a sheet 1 is nipped from the outside and the inside; a constant shape transparent sheet 5 arranged inside a peripheral frame 4 formed such that a plurality of the support materials 2 and the press materials 3 are attached on the sheet 1; and a lock material 6 to securely nip the constant shape transparent sheet 5 between the peripheral frame 4 and the lock material. Further, when the see-through window is attached to the sheet 1, a plurality of the support materials 2 and the press materials 3 are attached to the sheet 1 before the sheet 1 is cut to form the peripheral frame 4. Thereafter, the sheet 1 inside the peripheral frame 4 is cut for removal, and the constant shape transparent sheet 5 is arranged in an opening part 8 formed through the cutting for removal.