The present invention relates to a coating composition for a dielectric insulating film comprising a) an organosiloxane polymer, b) first metal ions selected from the group consisting of Rb ions, Cs ions, and a mixture thereof, and c) an organic solvent, in which the first metal ions are comprised at 1 to 200 ppm based on the weight of the composition, a dielectric insulating film prepared therefrom, and an electric or electronic device comprising the same. A dielectric insulating film prepared from the coating composition of the present invention has an improved dielectric constant and superior mechanical strength and electric properties.