New methods for estimation of concentration and distribution of plutonium in (Th,Pu)O₂MOX fuel samples have been attempted by spectroscopic analysis of SSNTD based alpha images using UV–Vis spectropho-tometry and photoluminescence spectroscopy. (Th,Pu)O₂ MOX fuel samples having a large range of PuO₂ concen-tration, were subjected to this study and found beneficial when compared with the conventional analysis of alpha autoradiographs. UV–Vis absorbance and photolumines-cence of the alpha autoradiograph showed linear decrease proportionally to PuO₂% in the fuel sample. Optical band gap was found to proportionally increase with PuO₂%in the fuel sample which was revealed in UV–Vis spectrophotometry.