SrFe 12 O 19 -MWCNTs composites with different MWCNTs content were synthesized by sol–gel method. The results of X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM) analyses demonstrated that the SrFe 12 O 19 nanoparticles were immobilized on the external surfaces of the CNTs. Vibration sample magnetometer (VSM) and Network vector analyzer measurements indicated that 6wt.% SrFe 12 O 19 -MWCNTs composites possessed the best magnetic and wave absorbing properties.