In the present work, polyester fabric with protective and magnetic properties is introduced using mixture of micro magnetic carbonyl iron powder and nano carbon black through pad-dry-cure method and sputter coating with aluminium (Al). This leads to X-band microwave absorbing properties as the great demand for protective garment. The morphology, static magnetic and X-band microwave absorbing properties of the treated fabrics were characterized by field emission scanning electron microscopy, vibrating sample magnetometer and vector network analyzer in the range of 8.2–12.4 GHz. Normal-angle X-ray diffraction was used to study the crystalline structure of treated PET fabric. Compared with the blank polyethylene terephthalate fabric without Al sputter coating, the presence of nano carbon black and carbonyl iron powder on the polyethylene terephthalate fabric sputter coated with aluminum exhibited higher microwave absorbing properties particularly in the primary range of 8.2–12.4 GHz. The results in the whole frequency range investigated were remarkable; however, the reflection loss was found to be lower than −5.9 dB in the entire frequency. The maximum reflection loss value was reached to −7.7 dB at the frequency of 8.2 GHz. Overall, the co-application of nano carbon black and carbonyl iron powders on the polyethylene terephthalate fabric opens up a new coating method for X-band microwave absorbing properties.