The invention discloses a high-voltage lithium cobalt positive electrode material and preparation method and application thereof. The high-voltage lithium cobalt positive electrode material comprisesan inner layer and a coating layer, wherein the inner layer is lithium cobalt particle core gradiently doped with nickel and aluminum, the doping content of the nickel in lithium cobalt particle is gradually reduced from inside to outside, the doping content of the aluminum in the lithium cobalt particle is gradually increased from inside to outside, the coating layer is a lithium cobalt compositeoxide containing M' element, and M' is selected from one or more of Ni, Mn, Al, Ti, Y, Zr, La, P, Nb, Sb and Ce. Meanwhile, the preparation method and application thereof of the high-voltage lithiumcobalt positive electrode material is also provided. The lithium cobalt material has better structure stability under a high voltage, higher discharging specific capacity and excellent cycle property.The preparation method and process of the lithium cobalt material is simple, and the operation process is controllable.