Sr3Ti2O7, which was known to a Ruddlesden-Popper phase as a layered perovskite-type oxide, was synthesized by the solid-state reaction method (SSRM) and polymerized complex method (PCM) in order to decompose pure water into hydrogen and oxygen without any co-catalyst. Under ultra-violet (lambda < 400 nm) irradiation, Sr3Ti2O7 catalyst prepared by the PCM was found to show promising results compared with that prepared by SSRM. When Ni was loaded onto Sr3Ti2O7 catalyst prepared by the PCM, this photocatalytic activity drastically increased. The highest activity was obtained by the loading of 3 wt.% of Ni. Moreover catalyst prepared by the PCM was also found to improve the stability of catalytic activity against long periods of photoirradiation. (c) 2005 Intemational Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.