By using the method of transmission electron microscope (TEM) the fractal structures were found in the colloid aggregates and colloidal particles of the highly sulfonated polyaniline

which is an important processable conductive polymer.In the present paper the concept and the mathematical model of fractal have been introduced into the studies of conjugated polymers.The colloid aggregates appear as an open dendritic structure and its growing process can be analoged by the diffusion limited cluster aggregate (DLCA) model. The analog pattern by computer and the theoretic fractal dimension are consistent with the experimental results.Since the colloidal particle is generated in the flatterning field of the dispersion media

the screening effect is weakened

and the colloidal particle is a spheroidal structure

which is deser than the colloid aggregates.The random rain(RR)model can be applied here and the analog gragh is in agreement with the TEM image.