Homogeneously　dispersed　ultrafine　CoFe2O4　nanoparticles　embedded　within　N-doped　carbon　nanofibers　(named　as　CFO@NCNFs)　have　been　fabricated　via　electrospinning　and　following　heat　treatment　procedures.　The　dielectric　and　magnetic　parameters　of　CFO@NCNFs/paraffin　wax　composites　are　regulated　through　adjusting　the　concentration　of　CoFe2O4　to　obtain　good　impedance　matching　and　excellent　microwave　absorption　(MA)　properties.　Benefiting　from　the　unique　structure　involving　CoFe2O4　@onion-like　carbon　nanospheres　and　3D　conductive　NCNFs　network,　as　well　as　the　synergistic　mechanism　between　ultrasmall　magnetic　CoFe2O4　nano-particles　and　light　mass　dielectric　NCNFs.　The　CFO@NCNFs-5　exhibit　outstanding　MA　properties　at　only　20　wt%　filler　loading　and　minimum　reflection　loss　(RL)　achieves-47.9　dB　(surpass　99.9%　MA)　at　9.2　GHz　with　a　thin　thickness　of　merely　1.7　mm,　and　the　corresponding　effective　absorption　bandwidth　(RL　＜-10　dB)　achieves　5.4　GHz　(6.5-11.9　GHz).　Moreover,　the　effective　absorption　bandwidth　(EAB)　can　be　obtained　in　multiband　(3.9-18.0　GHz)　by　adjusting　the　thickness　of　sample　layer.　Our　work　indicates　that　the　appropriate　incorporation　of　ultrafine　CoFe2O4　nanoparticles　encapsulated　in　NCNFs　is　a　versatile　and　high-efficiency　strategy　to　integrate　lightweight　and　excellent　properties　of　magnetic　carbon-based　absorbers.