The invention relates to a holder for cylindrical bending of an X-ray grid (15), where the grid holder supports the X-ray grid with supporting elements (5a-b, 7a-b, 8a-b, 9a-b, 10a-b) arranged along five supporting lines (14a-e) being parallel to by separated from each other. Moveable supporting elements (8a-b) positioned along a mid supporting line (14c) are arranged to raise when moveable supporting elements (9a-b, 10a-b) positioned along outermost supporting lines (14a-b) are lowered, while fixed supporting elements (5a-b, 7a-b) positioned along the remaining two supporting lines stay fixed. In one embodiment, the moveable supporting elements (9a-b, 10a-b) are moveably arranged along the sides of the grid holder and are provided with devices (23) for achieving raising or lowering of the grid when the moveable supporting elements are moved along the sides of the grid holder. The devices (23) for achieving raising or lowering of the grid may be constituted by slanted grooves (23) in the moveable supporting elements, where the grooves are arranged to cooperate with pegs (16a-b, 17a-b, 18a-b) on the grid. In another embodiment, the moveable supporting elements (9a-b, 10a-b) are mechanically connected to each other, such that all the moveable supporting elements move simultaneously. The fixed supporting elements (5a-b, 7a-b) may be constituted by rails at the bottom and at the lid of the grid holder facing each other.
