Nano-sized Eu-doped YAG phosphor particles were synthesized by a mixed solvo-thermal method using the stoichiometric amounts of inorganic aluminum and yttrium salts under moderate synthesis condition (300°C and 10MPa). The formation of YAG:Eu was investigated by means of XRD, TEM and TG–DTA. The effects of process conditions of the mixed-solvo-thermal method on the crystallinity, morphology and luminescent properties of phosphor particles were investigated. The crystalline YAG:Eu nanophosphors showed an orange-red emission with 5 D 0 – 7 F 1 as the most prominent group. The excitation and emission intensity increased with increasing the reaction temperature due to the higher crystallinity.