Ternary nanocomposite systems of poly(vinylidene fluoride)/magnetite/carbon nanotube (PVDF/Fe 3 O 4 /CNT) and poly(vinylidene fluoride)/magnetite/graphene (PVDF/Fe 3 O 4 /GN), were prepared using high shear twin screw compounding followed by compression moulding. The electromagnetic (EM) microwave absorption properties of the nanocomposites were investigated in the frequency range of 3-10 GHz. PVDF/Fe 3 O 4 /CNT samples with the thickness d = 0.7 mm present a minimum reflection loss (RL) of -28.8 dB at 5.6 GHz, while all the RL values in the measurement frequency range 3-10 GHz are lower than -10 dB. PVDF/Fe 3 O 4 /GN with a thickness of 0.9 mm, presents a minimum RL of -22.6 dB at 5.4 GHz, while all the RL values in the measurement frequency range 3-10 GHz are lower than -10 dB as well. The excellent microwave absorption properties of both nanocomposites, in terms of minimum RL value and broad absorption bandwidth, are mainly due to the enhanced magnetic losses. The results indicate that the ternary nanocomposites studied here, can be used as an attractive candidate for EM absorption materials in diverse fields of various technological applications, not only in the frequency range 3-10 GHz, but also at frequencies <3 GHz for PVDF/Fe 3 O 4 /CNT and >10 GHz for PVDF/Fe 3 O 4 /GN with a realistic thickness of close to 1 mm.