PANI/AgCl and PANI/BaSO4 nanocomposites were synthesized in reverse micelle with sodium bis(2-ethylhexyl)sulfosuccinate (AOT) as anionic surfactant. The influences of synthesis conditions including stirring and experimental procedure on the morphology of PANI/BaSO4 were investigated. The morphology of nanocomposites is observed by transmission electron microscope ( TEM), and electrical conductivities were measured by four-probe method. The structures were determined by UV-vis, IR spectra and X-ray diffraction analysis. These results show that reverse micelle is an effective nanoreactor for preparing organic-inorganic nanocomposites.