A part mounting facility is provided with substantially U-shaped conveyance paths having return bends, and the substantially U-shaped conveyance paths are formed by providing conveyance paths, which are in part mounting work regions, with the return bends. The substantially U-shaped conveyance paths are connected to each other, and the upstream-most substantially U-shaped conveyance path among the connected substantially U-shaped conveyance paths is connected to the downstream-most substantially U-shaped conveyance path to enable a workpiece conveyance dolly to circulate along the conveyance paths.