Designing the structure with dielectric loss and magnetic loss integrated contributes to expansion of microwave absorption bandwidth. Nanohybrid materials composed of iron oxide (Fe3O4) and multiwalled carbon nanotubes (MWCNTs) were prepared through a newly electrostatic attraction method as high-performance microwave absorbers in the 2-18 GHz band. The nanohybrids are characterized by transmission electron microscopy, X-ray diffraction, and vector network analysis. Microstructural analysis showed that Fe3O4 and MWCNTs were well-connected through electrostatic interaction in the nanohybrids. The experimental results indicated that MWCNTs/PEDOT: PSS/Fe3O4 possessed higher reflection loss and broader absorption bandwidth than MWCNTs. MWCNTs/SDBS/Fe3O4 had better matching of dielectric loss and magnetic loss, the absorption bandwidth below - 10 dB was up to 8 GHz. This work further reveals that the novel electrostatic attraction method could be efficiently enlarged electromagnetic wave attenuation performance in absorb materials.