The nanocomposites of multi-walled carbon nanotubes (MWCNT)/SrMnxCuxZr2xFe12-4xO19 (x=0.0, 0.2, 0.3, 0.4 and 0.5) were fabricated. The X-ray diffraction patterns (XRD) confirmed the formation of M-type hexaferrites crystal structure. Fourier transform infrared (FTIR) spectroscopy has been used to consider the chemical bonds in the nanocomposites. From field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), the fabrication of the nanocomposites has been confirmed. The vibrating sample magnetometer (VSM) was used to investigate magnetic properties of the nanocomposites. Microwave absorption properties have been investigated by the vector network analyzer. It is found that the nanocomposites with x > 0.3 and 7% weight percentage of MWCNT possess the wide bandwidth of 6 GHz. The nanocomposite with the chemical composition of SrMn0.4Cu0.4Zr0.8-Fe10.4O19-MWCNT has the highest reflection loss, and as a result, it is the most appropriate material among these samples to be used as an electromagnetic wave absorber. (C) 2016 Elsevier Ltd. All rights reserved.