The invention discloses an olivine-shaped structure LiNxPO4 surface modification lithium ion battery high-nickel laminated cathode material and a preparation method thereof. The chemical formula of the lithium ion battery high-nickel laminated cathode material is LiNiaCobM1-a-bO2, and the LiNxPO4 is a surface modification layer olivine-type material. The preparation method comprises the following steps: firstly, through a liquid-phase co-precipitation method and a high-temperature solid sintering method, preparing a pure-phase lithium ion battery high-nickel laminated cathode material; then, utilizing a method capable of combining a sol-gel method with a low-temperature sintering method to evenly coat and dope olivine-shaped structure LiNxPO4 to the surface of the high-nickel laminated cathode material surface. The olivine-shaped structure LiNxPO4 is used for carrying out surface modification on the lithium ion battery high-nickel laminated cathode material, the long-term cycling stability and the high-temperature performance of the material can be effectively improved, and the non-reversible deformation of the prepared material in a circulation process is inhibited. In addition, the preparation method has the advantages of being simple in operation, friendly in environment and suitable for industrial production.