In the preparation of high-quality polymeric carbon nanocomposites, the full compatibility of carbon nanotubes as the filler with the matrix polymer is required. For such a purpose, an aminoterminated polyimide, specifically designed to be structurally identical to the matrix polymer, was synthesized and used in the functionalization of carbon nanotubes. The functionalized carbon nanotube samples were analyzed and studied by using a series of techniques, and the results are presented and discussed. These nanotube samples and the matrix polyimide are soluble in the same organic solvents, allowing their intimate mixing in solution and the subsequent fabrication of polyimide-carbon nanotube composite films via wet-casting. According to results from the spectroscopic and electron microscopic characterizations, the carbon nanotubes are homogeneously dispersed in the nanocomposite films.