The invention relates to a nanometer polymethyl siloxane low-dielectric material, which uses mesh silicon-oxygen tetrahedron as main body at 500-1500 thick, and comprises silicon sheet layer and polymethyl siloxane film layer, wherein the film layer has holes whose diameter is 8-12nm, whole rate is 12-30% and the dielectric constant is 2.5-2.1. And the invention also provides a relative production, which comprises: said material can be used as the insulated material between signal layer, dual layer or multilayer metallic wires, to reduce the capacity between connected layers and the resistance of multi-layer core copper wires; and its mechanical property and processing property are higher than traditional CVD silicon dioxide. |