This paper reports the site-selective excited emission

fluorescence and photoluminescence excitation spectroscopy of cubic Gd

2

O

3

:Eu

3+

nanocrystals with diameters of 15

23

135 nm.The intensity distribution of photoluminescence spectra of Gd

2

O

3

:Eu

3+

nanocrystal depends on the size of nanocrystal

as a result of strong quantum confinement effect.The position of charge transfer band(CTB)calculated by Jorgensen formula is consistent with the experiment results.The emission peaks of C

2

and S

6

sites Eu

3+

in cubic Gd

2

O

3

:Eu

3+

are dissolved by the site-selective spectra excited with wavelengths in the CTB.The photoluminescence excitation spectra of C

2

and S

6

sitesEu

3+

CTB are worked out through the site-selective excitation spectra and photoluminescence excitation spectra.Itagrees well with the experiment results.