The energy levels of Pr3+ in SBN crystal are determined by means of absorption spectra and fluorescence spectra. The fluorescence band exhibits a double peak due to Pr3+ ions at different sites in SBN crystal. This shows that the multiphoton relaxation of 3Ｐ0→1Ｄ2, plays a dominant role in the radiationless transition of 3Ｐ0 state of Pr3+ ion by analysing the relation between the fluorescence lifetime and the sample temperature.