Water-cast nanocomposite films formed by poly(ethylene oxide) (PEO) and Laponite clay were found to display three characteristic levels of structure with large scale orientational order.The first level with the length scale of ca.40 nm was the PEO-intercalated clay lamellar bundles which tended to stack perpendicularly to the film surface.The second level with the characteristic length scale of 1.8 nm was associated with the alternating layer stacking of clay platelets and PEO sandwiched between the clay particles perpendicular to film surface.