4-(4'-Methoxyphenyl)urazole (MPU) was prepared from 4-methoxybenzoic acid in five steps. The reaction of monomer MPU with n-isopropylisocyanate was performed at room temperature in N,N-dimethylformamide solution, and the resulting bis-urea derivative was obtained in high yield and was finally used as a model for polymerization reaction. The step-growth polymerization reactions of monomer MPU with hexamethylene diioscyanate, isophorone diioscyanate, and toluene-2,4-diioscyanate were performed in NN-dimethylacetamide solution in the presence of pyridine as a catalyst. The resulting novel polyureas have an inherent viscosity (eta(inh)) in a range of 0.07-0.21 dL/g in DMF and sulfuric acid at 25degreesC. These polyureas were characterized by IR, H-1-NMR, elemental analysis, and TGA. Some physical properties and structural characterization of these novel polyureas are reported.