Honeycomb structural rGO (rGH)was constructed by taking Al2O3 honeycomb as template, andMXenewas then self-assembled on the rGH via electrostatic adsorption, to obtain honeycomb structural rGO-MXene (rGMH). Afterwards, the rGMH/epoxy nanocomposites with outstanding electromagnetic interference (EMI) shielding performance were successfully prepared by addition of epoxy resin. The introduction of 3D rGMH can fully play synergistic effects of rGO and MXene, to greatly improve the electrical conductivity (σ) and EMI shielding effectiveness (EMI SE) values of rGMH/epoxy nanocomposites. With the same loading of MXene, the σ and EMI SE values of rGMH/epoxy nanocomposites decrease with the increase of honeycomb cell size. Significantly enhanced σ (387.1 S/m) and EMI SE (55 dB) values are achieved when applying the cell size of 0.5 mm with 1.2 wt% rGO+3.3 wt% MXene loading, which are respectively 2978 and 5 times of rGM/epoxy nanocomposites (σ of 0.13 S/m, EMI SE of 11 dB) at the same loading of directly blending rGO-MXene fillers.