High efficiency microwave absorption (MA) materials with tunable electromagnetic (EM) features have been highly sought. However, it is still a challenge to achieve multi-bands absorption performance by simple optimizing the chemical composition of MA materials. Herein, a simple solvothermal method was used to embed magnetic Fe3O4 nanoclusters on MoS2 nanosheets, in which magnetic nanoclusters were quantitatively customized. More importantly, the MA frequency and MA properties of the material are highly tailored, and multi-bands absorption is achieved. The minimum reflection loss (RL) of Fe3O4/MoS2 composite reaches −87.24 dB and is about 4 times more than pure MoS2 nanosheets. The effective absorption bandwidth reaches 5.52 GHz (≤-10 dB). These desirable properties result from the introduction of appropriate magnetic Fe3O4 nanoclusters, which provide optimal synergistic effect of dielectric and magnetic losses. This result provides a feasible idea for designing high efficiency MA materials with tunable EM features in the future.