Аннотация:In this work, investigation of the spectroscopic parameters of the luminescence of Yb3þ ions in single crystalline films of Lu3Al5O12 and Y3Al5O12 garnets was performed using the synchrotron radiation excitation with the energy in the range of Yb3þ charge transitions (CT), exciton range and the onset of interband transitions of these garnets. The basic spectroscopic parameters of the Yb3þ CT luminescence in LuAG and YAG hosts were determined and summarized with taking into account the differences in the band gap structure of these garnets.