In order to transform the diamagnetism of expanded graphite (EG) to ferrimagnetism and improve its electromagnetic interferential capability, nano γ-Fe2O3/EG magnetic composite materials was prepared by sol-gel and low temperature self-combustion technique. The as prepared samples were characterized by SEM, XRD and Magnetic hysteresis cycle test. The results indicated that the composite materials had ferrimagnetism property after the embedding of γ-Fe2O3, but the average conductivity of the composites decreases gradually with the increase of γ-Fe2O3. Different mixing ratio of ferrite gel and graphite intercalation compounds produced ferric oxide with different crystal form and shape. When the content of ferrite sol was low, spherical γ-Fe2O3 with the mean size of 31.69nm was formed, and spread unevenly on the surface and interformational micelles of EG. High content of ferrite sol (83wt%) produced more perfect crystal γ-Fe2O3 of pentahedron shape with the mean size of 44.68nm, and a few of α-Fe2O3 occurred which lead to the decline of the magnetic property of the composite materials.