An efficiency electromagnetic interference (EMI) shielding composite with low microwave reflection was fabricated by introducing nickel coated ultrahigh molecular weight polyethylene particles (UHMWPE@Ni) into ground tire rubber (GTR) matrix. Chain-like carbon black (CB) aggregates in GTR domains connected discontinuous Ni layers to form a hybrid conductive network. The remarkable EMI shielding effectiveness (SE) and low reflection characteristics of GTR/UHMWPE@Ni composites were attributed to the well-connected Ni–CB hybrid conductive network with both magnetic hysteresis loss and electrical loss, and the multi-interfaces structure induced by the selectively distributed Ni layer at the interface between UHMWPE and GTR. With only 1.04 vol% Ni content, the EMI SE of GTR/UHMWPE@Ni composite reached 47.3 dB in X band. Because of the synergistic effect of the Ni–CB hybrid network, the power coefficient of reflectivity (R) of the composite was as low as 0.58. The result indicated that our work provided a feasible strategy to fabricate efficient electromagnetic shielding materials with low microwave reflection.