Al2O3 nano-particles were coated on the surface of LiNi1/3Co1/3Mn1/3O2 powder using a sol-gel method. The as-prepared Al2O3 nano-particle was identified to the cubic structure of Al2O3. The average size of the isolated Al2O3 nano-particles after heat treatments was calculated to be ~ 4 nm. The XRD showed that the structure of LiNi1/3Co1/3Mn1/3O2 was not affected by the Al2O3 coating. At 3 wt.% Al2O3 coatings on LiNi1/3Co1/3Mn1/3O2, the cyclic-life performance and rate capability were improved. However, heavier coatings (5 wt.%) on LiNi1/3Co1/3Mn1/3O2 dramatically decreased the discharge capacity and rate capability.