To provide a workpiece-inverting device high in work efficiency while including an electric support device for supporting a workpiece.

In the workpiece-inverting device 1 including workpiece rotation-supporting devices 10 for rotatably supporting a workpiece 5, the workpiece rotation-supporting device 10 includes a frame 11, a rotating body 20 supporting a predetermined part of the workpiece 5 and rotatably supported to the frame 11, and a power cable 30 for supplying power to the rotating body 20 from the outside; the frame 11 includes a plurality of support members 14 for rotatably supporting the rotating body 20, and a rotation drive device 17 connected to the power cable 30 and being a drive source for rotationally driving the rotating body 20; the rotating body 20 includes a rotary ring housing 21 supported to the support members 14, and an electric support device 23 installed on the rotary ring housing 21 for supporting the workpiece 5; and the rotation drive device 17 restricts the maximum rotation angle of the rotating body 20.