A novel high refractive index and highly transparent silicone resin-type material for the packaging of high-power light-emitting diodes (LEDs) is introduced, which was synthesized by hydrosilylation of vinyl end-capped methylphenyl silicone resin and methylphenyl hydrosilicone oil catalyzed by Karstedt's catalyst. The vinyl end-capped methylphenyl silicone resins were prepared by hydrolysis-polycondensation method from methylphenyl diethoxysilane (MePhSi(OEt)(2)), phenyl triethoxysilane (PhSi(OEt)(3)), and vinyl dimethylethoxy silane (Me(2)ViSiOEt) in toluene/water mixture catalyzed by cation-exchange resin. The vinyl end-capped methylphenyl silicone resins were characterized by H-1-NMR and Fourier-transform infrared. The performances of the cured silicone resin-type materials for LED packaging have been examined in detail. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013