The high activity of nano‐sized metal particles (NMPs) makes it easy to appear uncontrolled aggregation, which seriously affects Li/Na storage in electrode materials. Introducing adaptive substrates with proper affinity to NMPs is an effective strategy that optimizes the stability and capacity of the related electrodes. Herein, a comprehensive strategy for the fabrication of adaptive interfacial contacts between metallic Cu nanoparticles (NPs) and triphenyl‐substituted triazine graphdiyne (TPTG) substrates is reported. The sp C in the acetylenic linkers and N heteroatoms in the triazine groups synergistically stabilized the Cu NPs loaded onto the TPTG substrates. The stabilizing effect of the TPTG substrate induces a reversible lattice change of the Cu NPs during the charge–discharge process, thus efficiently facilitating the stable transfer of Li+/Na+. Intrinsic mechanism analysis indicates that the heterojunction contact interface of Cu NPs/TPTG provides branched charge transfer pathways from Li/Na to the Cu NPs and TPTG substrates, which synergistically adjusts the affinity to Li/Na atoms and ultimately improves the electrochemical performance in Li/Na storage. The investigation of the structure–property relationship deepens the understanding of the function of heterointerfaces, which is essential for optimizing the performance of energy storage devices.