The adsorption of H-2 on Ce-doped boron nitride nanotubes (BNNT) is investigated by using density functional theory. For the Ce/BNNT system, it is found that Ce preferentially occupies the hollow site over the BN hexagon. The results indicate that seven H-2 per Ce can be adsorbed and 5.68 wt% H-2 can be stored in Ce-3/BNNT system. Among nanotubes doped with metals, Ce exhibits the most favorable hydrogen adsorption characteristics in terms of the adsorption energy and the uptake capacity. Both hybridization of the Ce-5d orbital with the H-is orbital and the polarization of the H-2 molecules contribute to the hydrogen adsorption. Ce clustering can be suppressed by preferential binding of Ce atoms on BNNT, which denotes that BNNT as a hydrogen storage substrate is better than CNT due to its heteropolar binding nature. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.