Abstract Yttrium aluminum garnet (Y 3Al 5O 12, YAG) powders were synthesized by a sol–ge l combustion process from a mixed solution containing aluminum and yttrium nitrates. The thermal behavior of the precursor was determined by DSC–TG–MS techniques. FTIR and XRD techniques were used to characterize the processed precursor. It was found that excess citric acid and carboxylate mixture decomposed at about 400 °C to form carbonates. The YAG phase was supposed to nucleate directly from the amorphous precursor at about 800 °C. Mono-phase YAG crystallites could be formed without the formation of any intermediate phase at 900 °C.