Some of the recent topics on electrochemically formed thin films for high functionality devices were overviewed based upon our results. Characteristic microstructures of electroless-deposited cobalt alloy films for perpendicular magnetic recording media, electrolytic and electroless-deposited soft magnetic thin films, an electropolymerized active polymer films for batteries, ionic sensors and also inactive polymer films for biosensor devices, and porous silicon films formed on the surface of n-type single crystalline silicon by anodization for an electroluminescence device, were described and reviewed on the basis of our research works, and the correlation between them and their functional properties were discussed. It is demonstrated that the electrochemical processes have high potential for fabrication of the films for high functionality applications.