In this project, 1,4-bis(5-amino-1H-benzimidazol-2-yl)benzene and 1,3-bis(5-amino-1H-benzimidazol-2-yl)benzene, as novel monomers , containing benzimidazole group were prepared by the reaction of 1,2-phenyl diamine and terephthalic or isophthalic acid. Novel thermally stable aromatic poly( benzimidazole -amide )s )PBAs(, have been synthesized by low- temperature polycondensation of synthesized diamines and several different diacid chlorides. For this purpose, optimized conditions in term of reaction time and temperature were studied and the influence of the time of reaction on the inherent viscosity and the yield of the PBI were examined. The resulting PBIs exhibited good yields, high thermal stability with inherent viscosities ranging between 0.45 and 0.59 dL/g and are soluble in polar aprotic solvents. The synthetic polymers were characterized by FT-IR, 1 H-NMR, elemental and thermogravimetric analysis (TGA) techniques, differential scanning calorimetry (DSC), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) analysis. Also novel aromatic poly(imide-benzimidazole)s, PBAs, have been synthesized by polycondensation of synthesized diamines and pyromellitic dianhydride. The resulting PBIs exhibited good yields with inherent viscosities ranging between 0.39 and 0.4dL/g and are soluble in polar aprotic solvents. The synthetic polymers were characterized by FT-IR, 1 H-NMR, elemental analysis. In order to existence of benzimidazole moieties in polymer’s structure, it is expected the polymers tend to complex formation with different metals. So, a series of novel nanocomposites, via sol gel complexation of synthesized poly(amide-benzimidazole) with Ag + or Cu 2+ ions followed by reduction to metals, were prepared. The resulting nanocomposites were characterized by FT-IR, XRD, TGA, FE-SEM, and TEM. The FE-SEM and TEM results indicated that the Cu and Ag particles were dispersed homogenously in nano scale in PBI matrix. Finally, to improve the dispersion and obtain the homogeneous distribution of ZnO nanoparticles in polymer matrix, the surface of nanoparticle was modified with silane coupling agent ?-aminopropyltriethoxyl silane )KH550) and was mixed with one of the prepared polymers. In this way, the organic chains of silane coupling agents can accomplish steric hindrance between inorganic nanoparticles and the process of agglomerate formation is extensively reduced as well as the hydrophobicity of the surface of nanosized ZnO is obviously enhanced. Novel poly(amide-benzimidazole)/ZnO nanocomposites (PBI/ZnO NCs) were prepared by embedding of different ZnO nanoparticle contents into polymer matrix via ultrasonic method as a facial and inexpensive route. The resulting nanocomposites were characterized by FT-IR, XRD, TGA, DSC, FE-SEM, SEM-EDX and transmission electron microscopy (TEM). From these results, it can be found that there is no primary chemical bonding between PBI and modified ZnO nanoparticles. Therefore, the comparatively weak interaction (secondary chemical bonding) such as hydrogen bonding between NH 2 groups of KH550 and N–H in PBI, unmodified –OH groups on the surface of ZnO nanoparticle with amide (C=O) and benzimidazole groups of PBI. Also, the FE-SEM and TEM results indicated that the ZnO particles were dispersed homogenously in nano scale in PBI matrix. TGA confirmed that the thermal stability properties of the polymer were improved.