This invention relates to a method and board for forming a graphene layer, and more particularly, to a method of forming a high-quality graphene layer using high pressure annealing and to a board used therein. The method of forming the graphene layer includes forming a reaction barrier layer on a substrate layer, forming a metal catalyst layer which functions as a catalyst for forming the graphene layer on the reaction barrier layer, subjecting a board including a stack of the layers to high pressure annealing, and growing the graphene layer on the metal catalyst layer. This board is subjected to high pressure annealing before growth of the graphene layer, and the reaction barrier layer is formed using a material having high adhesion energy to the metal catalyst layer so as to suppress migration of metal catalyst atoms.