The main purpose of this work is proposing a new method of using non-isothermal formal kinetics analysis to predict the lifetime of luminescent complex materials. The Eu(III)-phenanthroline complex doped xerogel has been in situ synthesized by a catalyst-free sol-gel method. The photoluminescence spectra and TG curves of the xerogel verify the formation and decomposition of Eu(Ill)-phenanthroline complex in xerogel. The decomposition of the xerogel formally occurs in three steps. The Friedman and FWO isoconversional methods and multivariate non-linear regression method are used for formal kinetic analysis. The overall decomposition process below 800 degrees C is fitted by three-step consecutive reaction. The best fitted model for each step is F-n (n order reaction, the corresponding function f(alpha) is (1 -alpha)(n)). Correlation coefficient is 0.99956. The lifetime values of xerogel at different temperatures are predicted based on non-isothermal kinetic models by the 5% decomposition of europium organic complex. (C) 2005 Elsevier B.V. All rights reserved.