To provide a workpiece positioning apparatus for positioning even a special-shaped workpiece having an oblique side part without damaging it.

The workpiece positioning apparatus includes a supporting means forming a workpiece supporting face 10 for loading a plate-like workpiece W thereon, a transfer means for transferring the workpiece W along the workpiece supporting face 10 and a positioning means for stopping the workpiece W during the transfer by the transfer means at a predetermined position on the workpiece supporting face 10. The positioning means is equipped with stoppers 14, 15 which are protruded onto the workpiece supporting face 10 and brought into contact with an end face of the workpiece, a first traveling table 16 which is arranged below the workpiece supporting face 10 and movable in the workpiece transfer direction and a second traveling table 30 which is movable in the direction orthogonal to the workpiece transfer direction in a plane parallel to the workpiece supporting face 10. The stoppers 14, 15 are provided as accessories of upper parts of the first traveling table 16 and the second traveling table 30 respectively. The stoppers 14, 15 have polygonal contours, and are rotatably supported around the axis orthogonal to the workpiece supporting face 10.