Using the Taguchi method, the authors analyzed the optimum conditions for (Y3-xCex)Al5O12 (YAG:Ce) phosphor, which is prepared using the solid-state reaction method. The controllable factors used in this study consisted of the following: (1) the duration of milling, (2) the quantity of substitution, (3) the duration of sintering, and (4) the temperature of sintering. Under optimum conditions, a confirmation experiment was carried out, and the average photoluminescence (PL) intensity of YAG:Ce phosphor was found to be up to 270.84 (a.u.). The percentage contribution of each controllable factor was also determined. Most interestingly, the temperature of sintering is the most influential factor within current investigation range to the solid-state-prepared YAG:Ce phosphor, and its value of percentage contribution is up to 70.90%. Aside from this, through the optimum conditions, the average PL intensity of YAG:Ce phosphor can be substantially promoted from 193.88 (a.u.), the average PL intensity of YAG:Ce phosphor sintered at 1500 degrees C for 6 h that was usually used to sinter YAG:Ce phosphor. (C) 2011 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.