Low-density polyimide (PI)/clay aerogel composites were produced by freeze-drying of a poly(amic acid) ammonium salt/clay precursor suspension, followed by a multistep temperature-programmed imidization. The densities of the resulting aerogel composites were in the range of 0.04-0.09 g.cm(-3). With the increase of PI content, a more perfect "layer-strut" bracing structure was exhibited in the composites, which resulted in vastly improved mechanical properties. Polyimide did not intercalate the interlayer of clay, and the onset decomposition temperatures (T-d) of the aerogels were more than 410 degrees C. The obtained PI/clay aerogel composites show considerable promise in structural and high-temperature insulation applications.