Multiwall carbon nanotubes/epoxy and graphite nanoplatelets/epoxy composite materials (2-5 wt %) as well as the composite materials with barium hexaferrite as secondary filler (27 wt %) were prepared. Alignment of barium hexaferrite nanoparticles was performed by magnetic field action during polymerization process. Morphology, the electrical conductivity and shielding efficiency of the composite materials in the frequency range of 36-55.5 GHz were investigated. Optical and electron microscopy, standard 2- and 4-probe methods of electrical conductivity measurement and network analyzer were used for that purpose. The arguments about secondary filler addition and its alignment on electrodynamic properties of the obtained composite materials are given.