The invention discloses a water pump advanced motor coupler. The coupler is composed of raw materials including, by weight percent, 0.13 to 0.18% of nickel, 0.03 to 0.05% of manganese, 0.12 to 0.15% of nitrogen, 0.14 to 0.20% of oxygen, 2.12 to 2.30% of carbon, 0.15 to 0.24% of chromium, 1.58 to 2.10% of lead, 0.04 to 0.06% of titanium, 0.03 to 0.12% of molybdenum, 0.05 to 0.09% of tungsten, 0.03to 0.07% of aluminum and the balance iron. Chromium, titanium, aluminum and other elements in the coupler are chemically combined with oxygen and nitrogen, the stable oxide and nitride can be formed and mixed up with steel, internal shrinkage porosity and cavity defects are overcome, internal stress is improved, compactness is increased, steel strength is improved, lead is combined with the oxygenand nitrogen to enable the coupler to generate diamagnetism, in the rotating process, the coupler is not prone to magnetization, a heat conduction layer is attached to the surface of the coupler, heat generated in the rotating process can be rapidly transmitted and emitted out of a motor in the axial direction, a wear-resisting layer can effectively reduce friction between the coupler and a bearing, and the service life of the coupler is prolonged.