Abstract: Nanostructured（Y0.95Eu0.05）2O3 was synthesized through urea sol method，and n -（Y0.95Eu0.05）2O3 Particles / SiO2 aerogel assemblies were prepared by supercritical drying technique.The experimental results showed that we could achieve the maximum luminescence intensity by carefully choosing our optimal experimental conditions. When the molar ratio of Y3 + to Eu3 + equals 20:1，homogenous reaction for 4h，then under 680℃，4h annealing，the luminescence intensity of n -（Y0.95Eu0.05）2O3 was the maximum. In n -（Y0.95Eu0.05）2O3 / SiO2 aerogel assemblies，annealing under the same conditions，when the molar ratio of Si to 2Y equals 1: 7，the luminescence intensity of the assembly is the strongest，but it was still weaker than the luminescence intensity of n -（Y0.95Eu0.05）2O3 . And the phenomena of the luminescence intensity decrement of the assemblies against the nano - bulks and thered shift of the luminescence peaks were discussed.