In this work, FeSiAl–Fe3O4-GR/PLA composite printed wires were prepared by a two-step process of ball-mill mixing and melt extrusion using polylactic acid (PLA) as the base material, graphene (GR), FeSiAl and Fe3O4 as microwave absorbing enhancers. The results show that when the mass percentages of FeSiAl and Fe3O4 are 15 wt% and 15 wt% and the thickness is 5.3 mm, the composite material obtains the largest finite absorption bandwidth, at which time, the minimum reflection loss is − 48.08 dB and the absorption bandwidth is 3.52 GHz. When the mass percentages of FeSiAl and Fe3O4 are 20 wt% and 10 wt% and the thickness is 5.7 mm, the composite material has the strongest reflection loss, and the minimum reflection loss is − 50.62 dB and the absorption bandwidth is 3.28 GHz. Effective absorption of S, C, X and Ku band microwaves can be achieved by adjusting the thickness of the composite material. The excellent microwave absorption performance of the composites is mainly attributed to the effective synergy of the dual magnetic media, which enhances the absorption effects of interfacial polarization, dipole polarization, natural resonance, eddy current loss, and multiple reflections. Our research provides an effective way to prepare lightweight and efficient microwave absorbing materials in a green and simple process.