Abstract: The present invention provides a lithium ion battery and positive electrode material thereof. The positive electrode material includes a high nickel material having a chemical formula of LiNixM1-xO2 and a coating layer, wherein 0.5?X<1, M is selected from at least one of Co, Mn, Al, Mg, Ti and Zr, a specific surface area of the positive electrode material is 0.2 to 0.6 m2/g, and a residual lithium content on a surface of the positive electrode material is 200 to 1000 ppm. Compared with the prior art, the positive electrode material for lithium ion battery of the present invention is prepared by solid phase reaction, which not only can significantly reduce the residual lithium content on the surface of the positive electrode material, but also can avoid increase of the specific surface area of the positive electrode material for lithium ion battery.