PROBLEM TO BE SOLVED: To provide a device for fixing a sheet having good workability and working efficiency at low costs. SOLUTION: This device for fixing the sheet is structured as follows: a pair of first and second sheet-pressing frames 2, 3 inserted into a support frame 1 having a narrow-width opening part are pressed onto the inner wall of the support frame 1 with screws 4 having a diameter extending from its tip side toward its base end side, or pipe materials 11, 12. COPYRIGHT: (C)2005,JPO&NCIPI