Hierarchical hollow structure has demonstrated potential for enhancing electromagnetic (EM) attenuation and improving impedance matching, garnering significant attention for researching. Herein, we have successfully implemented compositional and structural engineering to fabricate hollow Mo₂C/C microspheres with controllable composition by coupling interaction between dopamine hydrochloride and ammonium molybdate. With the synergistic effect of composition and hollow structure, the strongest reflection loss intensity and broadest effective absorption of the optimized sample reach –70.2 dB and 6.2 GHz, respectively. The formation of hollow heterogeneous structures not only favors impedance matching feature, but also generates considerable contribution to EM attenuation capacity. Furthermore, radar cross-section simulation data indicate that hollow Mo₂C/C microspheres with compositional optimization and heterogeneous structures have broad prospects for practical applications.