A constructive system regarding a capacitance electric voltage sensor comprises a source electrode (110, 210), a shielding tubular body (120, 220), an electric field sensor (130, 230) and a mass of dielectric insulating material (140, 240). The electric field sensor (130, 230) comprises at least one first inner sheet (131, 231) and a second outer sheet (132, 232) superimposed and joined together, wherein said first inner sheet (131, 231) is made by means of a conductive metal material, wherein said second outer sheet (132, 232) is made by means of an electrically insulating material, and wherein said second outer sheet (132, 232) made of insulating material is constrained with respect to the inner face (124, 224) of the shielding tubular element (120, 220).