▎ 摘　　要

NOVELTY - Preparing ultrahigh directional thermally conductive carbon-based composite material comprises polishing the natural or synthetic diamond surface, carrying out ultrasonic cleaning, oxidizing the polished diamond film, pickling, heating, leaving the diamond carbon-carbon dangling bonds or terminating hydrogen, placing polymethyl methacrylate (PMMA) and graphene in deionized water, spreading, placing surface dangling bonds or hydrogen terminated diamond film in deionized water, forming graphene surface and plating. USE - The method is useful for preparing ultrahigh directional thermally conductive carbon-based composite material (claimed). DETAILED DESCRIPTION - Preparing ultrahigh directional thermally conductive carbon-based composite material comprises polishing the natural or synthetic diamond surface, carrying out ultrasonic cleaning to achieve automatic smoothness, oxidizing the polished diamond film, pickling to form high density ends of oxygen atom, heating under ultra-high vacuum or environment of hydrogen atmosphere to obtain a surface of carbon-oxygen bonds outside, leaving the diamond carbon-carbon dangling bonds or terminating hydrogen, placing polymethyl methacrylate (PMMA) and graphene in deionized water, spreading completely, placing surface dangling bonds or hydrogen terminated diamond in deionized water, forming graphene surface completely and plating on graphene to obtain the composite material.