This paper has investigated the absorption properties of multi-layer BaFe 12 O 19/ epoxy composites. Various Ba-ferrites were synthesized by the co-precipitation method followed by high-energy ball milling for the homogenizing and milling purposes. The microstructural, structural, loss-related behavior and magnetic properties were examined by the X-ray diffractometer, field-emission scanning electron spectroscope, network analyzer, and vibrating-sample magnetometer, respectively. The material indicated an enhancement in the saturation magnetization from 35.45 to 57.83 emu/g by increasing the heat-treating temperature (HT). The effects of the type and number of layers on microwave absorption behavior were obtained from the X-range (8 to 12 GHz). The ferromagnetic resonance and transmit-line theories were also employed to analyze these factors on the microwave absorption. These microwave absorbers were modeled and simulated by MATLAB. The simulations were carried out from 8 to 12 GHz to analyze the absorbers performance. Based upon these theories and experimental data, the microwave absorption can be altered solely by changing the materials between the layers. For instance, the maximum peak was increased from − 3 to − 15 dB by altering the as-synthesized ferrite powders to the completed ferrite powders (BaFe 12 O 19). Moreover, there was a sufficient match between experimental data and theoretical results.