The invention discloses a high-nickel ternary positive electrode material with monocrystal morphology and a preparation method of the high-nickel ternary positive electrode material. The preparation method comprises the following steps of (1) mixing a soluble nickel salt, a soluble cobalt salt, a soluble manganese salt, a precipitant and a complexing agent, and performing heating reaction to obtain a precursor; (2) mixing the precursor, a lithium compound and a doping metal compound, and sintering in an oxygen atmosphere to obtain a base material; (3) mixing the base material and a detergent,performing stirring, centrifuging and drying, and uniformly mixing with a coating agent to obtain a coated product; and (4) sintering the coated product to obtain the high-nickel ternary positive electrode material with monocrystal morphology. The high-nickel positive electrode material prepared by the method has morphology similar to that monocrystal, and is high in compaction density and energydensity, low in resided alkali amount and good in processability; and meanwhile, with the introduction of a doping element, a lithium ion battery prepared from the high-nickel positive electrode material has relatively high cycle property, and the cycle property and the safety of the material are also improved by the coating layer.