To facilitate installation construction without forming any slack in a sheet-like hanging smoke barrier.

The upper/lower edges of a heat-resistant resin sheet 1 are clamped in a U-cross-sectional grip frame 4 with its opening side narrowed between a pair of sheet grips 5 with the similar cross section, and a sheet grip plate 6 is pushed from the frame base side with fastening screws so that the sheet 1 is fixed by a pushing force applied between the sheet grips. When installing it to a fixing frame 60, the sheet 1 is supported on a sealing opening edge part 63 in the frame with a grip holer 10. A steady brace structure is formed by attaching a pair of joiners 25 for clamping the sheet to a bracing bracket. A rectangular bracket piece 16 at the top of the bracket is inserted from the sealing opening of the fixing frame base and rotated in the upper part of a support step 65, however, the length of the long side of the bracket piece is larger than the frame inner wall width to abut thereon and stop, the fastening bolt is tightened with the bracket abutting thereon and the bolt head part is made to abut on a partition wall 66 and fixed thereto.