To provide a vane bending machine in which, when vane plates in which the sizes of vanes, pitches, whether they are right-handed or left-handed or the like are different are worked, no preparation of many dies are required in accordance with their sizes.

Vane plates W are inserted into the spaces between the edge 11d of the first lower blade 11 and the edge 12b of the first upper blade 12, and between the edge 21d of the second lower blade 21 and the edge 22b of the second upper blade 22, and they are curved so as to form a part of a spiral shape. By changing the fitting position in the radial direction of each blade to each holder, vane plates W having different outside diameter and inside diameter can be managed, and, by changing the level difference H between the edge 11d and the edge 21d, the pitch of the spiral vane plates W can be changed.