A 2(K-1) factorial experimental design for spray granulation ZrO2(3%Y2O3)/(10-95)% Al2O3 composite system for precursor powders was performed. Initial suspensions were prepared by nano-scale adhesion of the alumina precursor on the surface of submicronic zirconia particles. The particles were ultrasonically dispersed at fixed optimal pHs corresponding to maximal Zeta potential. Lineal regression models were found that gave the best combination of spray-granulation parameters favoring high values of green density, specific surface area and low mean values of granules size. The explored experimental approach is promising in preparing suitable precursor powders of the composite system for many ceramic applications. (c) 2005 Elsevier B.V All rights reserved.