(Lu0.995-xCe0.005Lix)(2)SiO5 (x=0.0000-0.0100) phosphors were synthesized by sol-gel route, the luminescence intensity of the phosphor was improved by a factor of 23 at x=0.01 in comparison with the Li-free sample. This luminescence enhancement effect has been investigated by Ce L-III-edge X-ray absorption near edge structure spectroscopy. The underlying reason of enhanced luminescence was revealed. It is safely concluded that the enhanced luminescence by Li+ codoping in Lu2SiO5:Ce3+ phosphors is originated from the increase of the population of Ce3+. This result could also help us to understand the luminescence enhancement effect by Ca2+, Mg+ or Na+ codoping in Lu2SiO5:Ce3+ phosphors. (C) 2013 Elsevier B.V. All rights reserved.