A method for directly synthesizing graphene on a surface of a target object includes: forming a non-metal layer on a support substrate; disposing the target object in a space above the support substrate, which is opposite to the non-metal layer; and injecting a carbon precursor to form graphene on the surface of the target object to synthesize a graphene film, wherein the graphene is nucleated and grown by a decomposition of the carbon precursor, the carbon precursor is decomposed by heat with catalytic assistance from the non-metal layer, and a carbon atom from the decomposition of the precursor is anchored on the surface to form the graphene film.