Anilinium ions were intercalated into the clay layers of montmorillonite and platinum containing montmorillonite. Subsequent polymerization of aniline by electrochemical method to form polyaniline-montmorillonite composites. The cyclic voltammogram (CV) shows that polyaniline and Pt containing montmorillonite improve the response current of CV significantly. The analyses with EQCM, ESCA and ICP were also discussed.