Structure for Shielding Side Sill for Sliding Door Vehicle

A structure for shielding a side sill for a sliding door vehicle includes a lower rail mounted in an internal side sill space, a drive unit movably connected to the lower rail, and a shield structure including a cover unit having one end connected to the drive unit and guide rail units configured to guide the cover unit, wherein the cover unit covers the internal side sill space exposed in accordance with a movement of the drive unit.