▎ 摘　　要

NOVELTY - The preparation method of composite film involves (1) taking graphene oxide aqueous solution as raw material, adding boron nitride sheet, and ultrasonically processing or uniformly stirring to obtain mixed solution, and (2) pouring the mixed solution, and drying to obtain a graphene oxide-boron nitride composite film. USE - Preparation method of composite film. ADVANTAGE - The method enables preparation of composite film with high-in-plane thermal conductivity, and which maintains electrical insulation effect, by simple and environmentally-friendly processes.