The polyaniline multi-walled carbon nanotubes composite with core-shell structures was synthetized via in situ chemical oxidative polymerization, and the materials were characterized by physical and chemical methods. The PANI/WMCNTs was synthetized via in situ chemical oxidative polymerization with core-shell structures. The WMCNTs highly enhanced the conductivity of composites. The comopsites were more conducive to the intercalation and deintercalation of anions and cations. The much better performance as the cathode for lithium-ion cells was acquired for the composites. The composites are low cost and eco-friendly which have a good prospect in future.