A protected active metal electrode and a device with the electrode are provided. The protected active metal electrode includes an active metal substrate and a protection layer on a surface of the active metal substrate. The protection layer at least includes a metal thin film covering the surface of the active metal substrate and an electrically-conductive thin film covering a surface of the metal thin film. A material of the metal thin film is Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, or W. A material of the electrically-conductive thin film is selected from nitride of a metal in the metal thin film, carbide of a metal in the metal thin film, a diamond-like carbon (DLC), and a combination thereof.