In order to obtain a simple and low-cost electromagnetic shielding material, the 2D carbon fiber (CF) precast was loaded with graphene oxide (GO) by spraying method, and the boron-phenolic resin (BPF) was used as the precursor, and the graphene supported carbon fiber (GO/CF) was used as the precast. GO modified carbon/carbon composites (GO/C/C) were prepared by hot press molding method and carbonization process. X-ray Diffraction (XRD), scanning electron microscope (SEM), Raman spectrum, densitometer and vector network analyzer were used to characterize the composites. The results show that the surface morphology of GO/CF preform is the best when the load of GO is 0.1% and 0.3%. When GO content is 0.3%, the composites have the highest porosity and the lowest resistivity. When the load of GO is 0.1%, the total electromagnetic shielding efficiency of the composite in the X-band is the highest, reaching 43.84 dB, which is 28.3%higher than that of the blank sample, and has met the basic commercial requirements.