Inhibiting the formation of lithium (Li) dendrites for Li metal anode is of great significance to the practical application of high-energy-density battery systems. Herein, we report an artificial Li3PO4 solid electrolyte interphase (SEI) layer on a Li metal anode (LPO-Li) which fabricated by the spontaneous redox reaction of the Li metal and copper phosphate (Cu-3(PO4)(2)) in tetrahydrofuran (THF) organic solvent at room temperature. This stable Li3PO4 layer can act as a protective layer between the metallic Li and electrolyte to prevent side effects during cycling. The Li metal anode with the Li3PO4 layer can acquire optimize deposition of Li and enable a stable and prolonged cycling without formation of Li dendrites. When matching the LiNi0.6Co0.2Mn0.2O2 (NCM) cathode, the NCM/LPO-Li battery presents an excellent electrochemical performance.