A depth analysis spectra method for researching fluorescent and Raman spectra was developed since a self-absorption was often observed in fluorescent spectra of thick solid sample. The intensity change of self-absorption could be observed to explore the secrets of solid state spectra by depth analysis method. The Raman and fluorescent spectra of Nd3+∶YAG crystal were measured with 633nm of HN laser and 514.5nm of Ar+ laser. Some fluorescent lines which possess self-absorption were observed, whose intensity changes with depth of confocal plane. It shows that spatial resolution (depth analysis) method is a powerful experimental means for studying solid state spectroscopy.