Summary The structural and interfacial degradation of Ni‐rich cathode materials during the cycling continuously delays its commercialization of lithium‐ion batteries (LIBs). To overcome these drawbacks, we propose a MgHPO4‐modified LiNi0.8Co0.1Mn0.1O2 (M‐NCM) cathode material. From electrochemical analysis, M‐NCM takes the combining advantages of Mg doping and Li3PO4 coating. Interestingly, M‐NCM shows a better discharge capacity of 203.5 mAh g−1, delivering outstanding initial coulombic efficiency of 86.1% compared to the pristine LiNi0.8Co0.1Mn0.1O2. Additionally, M‐NCM displays advanced cycle performance with a superior capacity retention of 81.1% after 100 cycles. Furthermore, M‐NCM effectively suppresses interfacial undesirable reactions at electrode/electrolyte interface during cycling. Consequentially, this study finds that MgHPO4 surface modification can bring enhanced electrochemical performance of Ni‐rich‐layered cathode materials for high‐energy and long‐term LIBs.