The present invention relates to a method for fabricating an inductor and, more particularly, to a method for fabricating a spiral inductor used in a monolithic microwave integrated circuit on a silicon substrate using semiconductor fabrication processes. The method for fabricating an inductor, comprising the steps of: forming a first dielectric layer on a silicon substrate and forming a first metal wire on the first dielectric layer, wherein the first metal wire is in contact with an active element formed on the silicon substrate; and alternatively forming dielectric layers and metal layers, wherein the metal layers are electrically connected with an upper metal wire and a lower metal wire and wherein the metal layers are patterned using the dielectric layers as etching mask, whereby a metal corrosion is prevented by using the spiral dielectric pattern as the etching mask.