Abstract: The invention provides a dielectric material with low dielectric loss. The dielectric material comprises (i) 40˜80 parts by weight of polyphenylene ether resin having a Mw of 1000˜7000, a Mn of 1000˜4000 and Mw/Mn=1.0˜1.8; (ii) 5˜30 parts by weight of bismaleimide resins; and (iii) 5˜30 parts by weight of polymer additives, wherein the dielectric material has Dk of 3.75˜4.0 and Df of 0.0025˜0.0045. The dielectric material is suitably used in prepregs and insulation layers of a circuit board, because it has high Tg, low thermal expansion coefficient, low moisture absorption and excellent dielectric properties such as Dk and Df.