Abstract: Graphene/iron phthalocyanine(G/FePc) composites were prepared by co-grinding and hot-press molding. The microstructure of G/FePc composites was examined by SEM and the interaction between G and FePc was examined by XPS. It's found that FePc is uniformly absorbed on G and G/FePc composites form layer-like structure after solidification, which improves the heat resistance and wave absorbing properties. The effect of G content on the heat resistance and electromagnetic properties of G/FePc composites was further explored by TGA and vector network analysis, and the wave absorbing properties of G/FePc composites were simulated. The results show that the heat resistance and wave absorbing properties of G/FePc composites increase with G content increasing. When the G content is 5%(mass ratio), the char yield reaches 62.2% at 1 000℃, the maximum reflectivity reaches -30.5 dB with the thickness of 3.5 mm and bandwidth of reflectivity less than -10 dB is 1.38 GHz.