Because of its own good mechanical properties, nano-enhancement of the high performance polymers places greater demands on the nano fillers. In this study, the aromatic polyamide (PA) film containing benzimidazole moieties was further enhanced by the fluorinated graphene with high fluorine/carbon ratio and corresponding excellent thermal stability and dispersibility. The sec-amine -NH- in benzimidazole shows weak basicity and thus nucleophilic reactivity, which is supposed to react with the C-F bonds in fluorinated graphene sheets and form the C-N bonds covalently linking the macromolecules and graphene sheets. However, HCl in the PA solution would hinder the fluorine atoms being substituted by the -NH- in benzimidazole because it complexed with the imidazole ring and transformed the basicity of macromolecules to acidity. Here, pyridine was added to neutralize the HCl. Combining the catalysis of pyridine, PA molecules were in-situ covalently grafted on fluorinated graphene sheets, which was confirmed by fourier transform infrared spectroscopy, thermal gravimetric analysis and Raman spectroscopy, and resulted in the increasing tensile strength of composite films from 183 to 230 MPa.