Highly crystalline polyaniline (PANI) with elongated chain-like nanostructures 20-35 nm in diameter and 60-80 nm in length were prepared using sodium dodecylbenzenesulfonic acid (SDBSA) in ice medium withoutstirring. The synthesized polyanilines were characterized by SEM, FTIR, and UV-Visible spectroscopy andXRD measurements. The formation of polyaniline/SDBSA salts insoluble in reaction system without stirring isfound to be favourable for the formation of this clustered chain-like nanostructure. The temperature dependentconductivity measurement shows a thermally activated exponential behaviour of the chain-like polyanilinenanostructure. The melting point of the nanostructured polyaniline was found to be 253 °C.