Electromagnetic wave pollution has become a hidden danger to information security and human health．Microwave absorption materials are considered to be one of the most feasible measures to solve the problemof electromagnetic wave pollution． The graphene/barium ferrite nanocomposites were prepared by hydrothermal method and characterized by X-ray diffractometer，scanning electron microscope，vibrating sample magnetometer and vector network analyzer．The results reveal that when the thickness of the composite is 2 mm，the effective bandwidth can reach 6.8 GHz．When the frequency is 12.64 GHz，the minimum reflection loss is-41.66 dB． Through the comprehensive experimental design，the absorbing mechanism of nano-composite materials is studied from the experimental point of view，which is helpful to improve students’interest in scientific research and inspire students’innovative thinking．