We synthesized multi-walled carbon nanotube (MWNT)/polyaniline (PANI) nanocomposites from an oxidative dispersion. polymerization using poly (vinyl alcohol) (PVA) os a polymeric stabilizer. Purified MWNT whose metallic catalysts hove been removed in acidic media was applied. The formation of nanocomposites and their morphology ware confirmed by both scanning electron. microscopy (SEM) and transmission electron microscopy (TEM). Electro-rheological properties were further characterized by a rotational rheometer equipped with a high voltage generator.