Graphene is a promising contender to succeed the throne of silicon in electronics. To this goal, large-scale epitaxial growth of graphene on substrates should be developed. Among various methods along this line, epitaxial growth of graphene on SiC substrates by thermal decomposition of surface layers has proved itself quite satisfactory both in quality and in process reliability. Even modulation of structural and hence electronic properties of graphene is possible by tuning the graphene/SiC interface structure. The challenges for this graphene-on-SiC technology, however, are the abdication of the well-established Si technologies and the high production cost of the SiC bulk crystals. Here, we demonstrate that formation of epitaxial graphene on silicon substrate is possible, by graphitizing epitaxial SiC thin films formed on silicon substrates. This graphene-on-silicon (GOS) method enables us to form a large-area film of well-ordered sp2 carbon networks on Si substrates and to fabricate electronic devices based on the structure.