High temperature poly(p-phenylene biphenyltetracarboximide) nanocomposite films with inorganic particulates, which are applicable to the fabrication of microelectronic devices, were prepared from the poly(amic acid) and silica aerogels with a size of ca. 150 nm in diameter by solution blending and subsequent conventional polyimide film formation process. The structure and properties were measured. By the composite formation, the optical and dielectric properties were improved due to the low dielectric constant characteristic of silica aerogels, whereas the interfacial stress and thermal expansion coefficient were significantly degraded by a large disturbance in the polymer chain in-plane orientation caused by silica aerogels despite of their low thermal expansivity. This indicates that in the rigid type of polymer composites with inorganic particulates, the orientation of polymer chains still plays a critical role on the physical properties.