The zone-drawing method was applied to chemically synthesized polyaniline cast films of emeraldine base under various applied tensions and drawing temperatures. The changes in the microstructure and viscoelastic properties of the resulting films were investigated. It was found. that, the microstructure was strongly affected by the drawing temperature (T-d). The crystallinity, crystallite size, and orientation factor of crystallites, respectively, attained 42%, 23 Angstrom, and 0.975 for the film zone-drawn at T-d = 170 degrees C, whereas a further increase in the T-d brought about a decrease of these values. The viscoelastic measurements indicated that the dynamic storage modulus attained 12 GPa at room temperature and was 5 GPa at 280 degrees C for the film zone-drawn at T-d = 210 degrees C, which was comparable to that of the typical engineering plastics.