The present invention provides a method of modifying the nano-aluminium oxide using cold plasma, including: (1) the selection of different monomer loading pattern, i.e., direct loading or solvent-assisted loading based on the load rate of the monomer to be grafted on the surface of nano-aluminium oxide particles; and (2) apply the cold plasma treatment to the nano-aluminium oxide particles whose surface receive the load of the monomer to be grafted, wherein, the treating power is 10 W -150 W, time is 0.1s - 3,600s, temperature 10 - 400oC, and the cold plasma induces the monomers on the surface of nano-aluminium oxide particles to polymerize thus modifies the surface of nano-aluminium oxide.