4-[4'-(2-Hydroxy-1-naphtkylazo)phenyl]-1,2,4-triazolidine-3,5-dione (HNAPTD) (1) has been reacted with excess amount of n-propylisocyanate in DMF (N,N-dimethylformamide) solution at room temperature. The reaction proceeded with high yield, and involved reaction of both N-H of the urazole group. The resulting bis-urea derivative 2 was characterized by IR, H-1-NMR, elemental analysis, UV-Vis spectra, and it was finally used as a model compound for the polymerization reaction. Solution polycondensation reactions of monomer 1 with Hexamethylene diisocyanate (HMDI) and isophorone diisocyanate (IPDI) were performed in DMF in the presence of pyridine as a catalyst and lead to the formation of novel aliphatic azo-containing polyurea dyes, which are soluble in polar solvents. The polymerization reaction with tolylene-2,4-diisocyanate (TDI) gave novel aromatic polyurea dye, which is insoluble in most organic solvents. These novel polyureas have inherent viscosities in a range of 0.15-0.22 g dL(-1) in DMF at 25 degreesC. Some structural characterization and physical properties of these novel polymers are reported.