This paper relates to a process for preparation of polyaniline salts such as polyaniline-sulfate, polyaniline-nitrate and polyaniline-hydrochloride by emulsion polymerization pathway. Aniline was oxidized to polyaniline salt using benzoyl peroxide as an oxidizing agent in the presence of sulfuric, nitric, or hydrochloric acid by emulsion polymerization pathway. Polyaniline salts and their corresponding bases were characterized by infrared, electronic absorption, X-ray diffraction spectral techniques, scanning electron microscope, X-ray photoelectron, elemental analysis and conductivity measurement. The results of this study indicate that both acid and surfactant group are present in the polyaniline salt as dopants. The values of yield were found to be 59.6, 55.0 and 53.9% for polyaniline-sulfate, polyaniline-nitrate and polyaniline-hydrochloride salt respectively. Conductivity of the polyaniline-sulfate (0.08 S/cm) was found to be same as that of polyaniline-nitrate salt (0.08 S/cm) and however, one order of magnitude lower conductivity was obtained for polyaniline-hydrochloride salt (0.004 S/cm). The semiconducting range (10(-1) to 10(-4) S/cm) can be used for EMI shielding and antistatic applications. (C) 2004 Kluwer Academic Publishers.