▎ 摘　　要

NOVELTY - Preparation of graphene/carbon composite material comprises placing water-soluble starch in hydrothermal reaction kettle, sealing, placed into heater case, removing from kettle, and quenching with water; adding starch hydrolyzate, placing in a conical flask, adding graphite oxide, and ultrasonically dispersing; placing again into reactor, sealing, heating to 200 degrees C, and naturally cooling; cooling to room temperature, adding activator, and drying; carbonizing and activating and natural cooling; and fully washing. USE - Method for preparing graphene/carbon composite material (claimed) used for electrochemical supercapacitors. ADVANTAGE - The method is simple and can improve electrochemical performance of composite material.