In this project, 5-hydroxyisophthalohydrazide, as a monomer, containing phenolic group was prepared intwo steps. In first, 5-hydroxyisophthalic acid convert to diethyl 5-hydroxyisophthalate as a diester intermediate. Then, this diesterreactedwtihhydrazine to givemonomer. A series of novel hydroxyl containing polyhydrazides(PHs) were prepared by the solution polycondensation of new dihydrazide monomer with several aromatic diacid chlorides. 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 PH were examined.According to these results, one equimolar of synthesized dihydrazide with one equimolar of different diacid chlorides were reacted first for 6h at 0 o C and then for 12 h at room temperature and the resulting mixture was precipitated in methanol to obtain polymers. The resulting PHs exhibited good yields, high thermal stability with inherent viscosities ranging between 0.30 and 0.65dL/g and were soluble in polar aprotic solvents. The synthetic polymers were studied and characterized by FT-IR, 1 H-NMR, elemental and thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) analysis. This polyhydrazids have ability to convert to related sulfonatedpolyoxadiazoles. Because of the presence of phenolic groups in the main chain that can oxide in a specific electrochemical potential, the polymers are electrochemical active. Then the polymers were characterized and investigate with cyclic voltametric and electrochemical impedance. In the second part of the project, a sulfonatedpolyoxadiazole were synthesizedby the polycondensation of 5-hydroxyisophthalic acid in poly(phosphoric acid) and presence of hydrazine sulfate. Conditions in term of reaction time and other terms were optimized.The ion exchange capacity (IEC) and sulfonation degree (SD%) were high and show the polymer chains were sulfonated in reaction conditionin good yield. Acids groups on polymer chains were neutralized which shows a high ability to absorb water as a hydrogel. The polymerwas characterized by FT-IR, elemental and thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and field emission scanning electron microscopy (FE-SEM) analysis.In the next parta high molecular weightsulfonatedcopolyoxadiazole wassynthesizedby the polycondensation of 5-hydroxyisophthalic acid and 4,4’-diphenylether dicarboxylic acid in poly(phosphoric acid) and presence of hydrazine sulfateat high temperatures. The reaction conditions were optimized and the polymer was characterized by FT-IR, 1 H-NMR, elemental and thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and field emission scanning electron microscopy (FE-SEM). The high thermal stable polymerwas coverted to membrane by casting method. The membrane shows good mechanical properties. The ion exchange capacity (IEC) and sulfonation degree (SD%) were high and show the polymer chains were sulfonated in reaction condition in good yield. Proton conductivity was 0.02 S.cm-1 in goodquantity. This amount of conductivity is good and high in compare to Nafion ® and other same membranes.This fast and high yield procedure that producesa heat resistance andhigh proton conductive membrane is not only of technologically but also of economicallyconvenience compared to multiple-stage and same process.