The visible region absorption spectra and photoluminescence spectra excited by 514.5 nm and 488.0 nm laser for the sesquioxides of the rare earths Y 2O 3, La 2O 3 and Lu 2O 3, which were finely divided powders of spectrographic purity, have been measured. When 488.0 nm and 514.5 nm laser lines were used as pumping excitations, the luminescence was abserved from Y 2O 3 and Lu 2O 3, whereas the sample La 2O 3′s fluorescence was only excited by 488.0 nm laser line. Comparing the asorption spectra and photoluminescence spectra of them with that of other RE 2O 3, the results show that the luminescences of Y 2O 3, La 2O 3 and Lu 2O 3 arised from the sample′s trace impurity Er 3+ , Sm 3+ and Eu 3+ respectively.