Energy band structure, photoelectrochemical performances and photocatalysis activity of spinel Li4Ti5O12 are investigated for the first time in this paper. Li4Ti5O12 possesses more positive valence band potential and wider band gap than TiO2 due to its valence band consisting of Li-1s and Ti-3d orbitals mixed with O-2p. Li4Ti5O12 shows typical photocatalysis material characteristics and excellent photocatlytic activity under UV irradiation. (C) 2014 Elsevier Ltd. All rights reserved.