Display omitted •NRGO/Ni0.5Zn0.5Fe2O4 composite was fabricated by a facile two-step strategy.•Well-designed entanglement structure was clearly observed in the binary composite.•Complexing of NRGO notably enhanced the microwave absorption of Ni0.5Zn0.5Fe2O4.•The relationship between filler loading and refection loss was carefully clarified.•Strong absorption, broad bandwidth and thin thickness were simultaneously achieved. Nowadays, developing high-performance microwave absorbers with thin thickness, strong absorbing, broad bandwidth and low filler loading is of great importance for solving the problem of electromagnetic pollution. Herein, nitrogen-doped reduced graphene oxide/nickel-zinc ferrite (NRGO/Ni0.5Zn0.5Fe2O4) composite was synthesized using graphene oxide (GO) as a template by a facile two-step strategy. Results of morphology observations revealed that well-designed entanglement structure consisting of Ni0.5Zn0.5Fe2O4 microspheres and crumpled NRGO was clearly observed in the as-prepared NRGO/Ni0.5Zn0.5Fe2O4 composite. Moreover, the effects of complexing of NRGO and filler loadings on the microwave absorption properties of NRGO/Ni0.5Zn0.5Fe2O4 composite were carefully investigated. It was found that the complexing of NRGO notably enhanced the microwave absorption properties of Ni0.5Zn0.5Fe2O4 microspheres. Significantly, the obtained NRGO/Ni0.5Zn0.5Fe2O4 composite demonstrated the optimal minimum reflection loss of −63.2 dB with a matching thickness of 2.91 mm in the X-band and effective absorption bandwidth of 5.4 GHz (12.0–17.4 GHz) almost covering the whole Ku-band with a thin thickness of merely 2.0 mm. Furthermore, the relationship between filler loading and refection loss was carefully clarified. Besides, the underlying microwave absorption mechanisms of as-prepared composite were proposed. It was believed that our results could shed light on the design and fabrication of graphene-based magnetic composites as high-efficient microwave absorbers.