Abstract: Copolymers containing pyridine rings are synthesized by the solution polycondensation of 3,3′-diaminobenzidine (DAB), 2,3,5,6-tetraaminopyridinium (TAP) and 4,4′-dicarboxydiphenyl ether (DCDPE) with different proportions. The copolymers are characterized by FT-IR,1H-NMR, TGA and tensile tests. When the mole fraction of TAP in the two amine monomers are 0.1, 0.2 and 0.3, the inherent viscosities at 30 ℃ are 0.806, 0.816, 1.028 dL/g, respectively. The copolymers show good solubility in N, N-dimethylformamide (DMF), dimethyl sulphoxide (DMSO), N-methyl-2-pyrrolidone (NMP) and some inorganic acids like H2SO4. The copolymes can be completed in a short period, which have good thermal stability and mechanical strength.