In this work, Y2O3:Eu3+ thin film phosphors were prepared by electro-deposition method. The effect of Na+ and K+ ions on the photoluminescence properties of Y2O3:Eu3+ thin film phosphor was studied in details. It was found that the addition of Na+ and K+ ions could improve the photoluminescence intensity by 3 to 4 times. The highly improved photoluminescence intensity may be caused by different factors. The improved crystallinity and the increased optical volume caused by the flux effect of Na+ and K+ ions could be the major reasons for the enhanced photoluminescence intensity. It was also found that the average lifetime of Y2O3:Eu3+ thin film phosphors could be adjusted by the molar amount of Na+ and K ions. (C) 2011 Elsevier B.V. All rights reserved.