Polymerization of pyrrole was carried out in the intracrystalline tunnels of sepiolite adsorbing I 2 to obtain a linear polymer of pyrrole in the limited space of the tunnel. The composites of polypyrrole, sepiolite and I 2 (I 2 -SPy) were obtained. The polymerization of pyrrole took place in the inner space of the tunnels of sepiolite adsorbing a small amount of I 2 . On the other hand, using the sepiolite adsorbing a large amount of I 2 , the polypyrrole was formed on the sepiolite. Electrical conductivities of the resulting composites (I 2 -SPy) increased with an increase of the I 2 content. The existence of a polaron and a bipolaron in the composites was confirmed by EPR signals at g = 2.00 and strong absorption bands above 450 nm, respectively. The electric conductivity of the I 2 -SPy composites is attributed to the polaron and bipolaron in the sample.