Abstract: Polyaniline/Cds nanocomposite has been prepared using chemical oxidation technique. The prepared products were characterized by FT-IR, XRD and Transmission electron Microscopy and TGA thermogram. FTIR absorption band at 414 cm-1 indicated the presence CdS nanoparticles in the polymer matrix. The XRD study revealed the increased in crystalline nature of nanocomposite.TEM showed the CdS particles are in nanorange with the average diameter of 21 nm. Thermo gravimetric analysis clearly indicated the increased in thermal stability of nanocomposite than the pure PANI. The D.C electrical study of PAni/Cds nanocomposite clearly indicated that the CdS nanoparticles increased the electrical conductivity of polyaniline nanocomposite to 1.79x10-3 S/cm compared to the pure polyaniline (10-10 S/cm) and Silicon (10-4S/cm) semiconductors. Its electrical conductivity was found to be analogous with existing semiconducting metals [14].