Surface energies of indium doped ZnO were calculated to explain the polarized growth of ZnO nanodisks due to indium doping. Calculation results show that the surface energy of ZnO (0001) surface is much larger than that of ZnO (10 1 0) surface, leading to a preferred growth direction of  for pure ZnO. At a doping rate of 1/8, the surface energies of indium doped ZnO are greatly reduced, but the surface energy of (0001) surface is still larger than that of (10 1 0) surface. At a doping rate of 1/4, the surface energies are decreased further, and the surface energy of (0001) surface is lower than that of (10 1 0) surface. Hence, growth of ZnO along [10 1 0] direction is made possible by heavy indium doping.