The electronic structure and transport properties of In24M8O48 (M = Ge4+, Sn4+, Ti4+, and Zr4+) have been studied by using the full‐potential linearized augmented plane‐wave method and the semiclassical Boltzmann theory, respectively. It is found that the magnitude of powerfactor with respect to relation time follows the order of In24Sn8O48 > In24Zr8O48 > In24Ge8O48 > In24Ti8O48. The largest powerfactor is 2.7 × 1012 W/K2ms for In24Sn8O48 at 60 K, which is nearly thirty times larger than those of conventional n‐type thermoelectric materials. The origin of the different thermoelectric behavior for these compounds is discussed from the electronic structure level. It is found that, at low temperature, the dopant strongly affect the bands near the Fermi level, which consequently leads to their different thermoelectric properties. The electronic configuration and the difference in atomic number between the dopant and the host atom also play an important role on the thermoelectric properties of In24M8O48. Our calculations give a valuable insight on how to enhance the thermoelectric performance of In32O48. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011