PURPOSE: To make it possible both to improve molecular orientation of a thin film to be prepd. and to obtain high electric conductivity, by carrying out electrolytic polymn. of an electrolytic liq. contg. monomers or oligomers being capable of electrolytically polymerizing while a magnetic field is applied to the electrolytic liq.

CONSTITUTION: Electrolytic polymn. is carried out in an electrolytic liq. contg. monomers or oligomers being capable of electrolytically polymerizing (e.g., pyrrole as the electrolytically polymerizable monomer, tetra-n-butyl-ammonium perchlorate as a conductive salt and acetonitrile as a solvent are used to prapare the electrolytic liq.) while a magnetic field is applied. Thus it possible to improve molecular orientation of a highly conductive org. thin film obtd. and to obtain high electric conductivity. Therefore, effective conduction can be expected even for a small area and miniaturization and getting high-performance of electrodes, battery systems, batteries, semi-conductor elements, solar batteries and so on can be achieved.