This study leverages infrared thermal imaging technology to advance the field of stone cultural relics preservation by introducing a novel evaluation index—temperature variation (Tv)—that quantifies the degree of surface deterioration. Unlike previous studies that have focused primarily on detecting a single deterioration type, this study pioneered a comprehensive analysis of the interactions of multiple deterioration in stone cultural relic. A deeper understanding of the weathering mechanisms of stone cultural relics has been gained by examining the Tv on the surface of stone cultural relics during heating and cooling, and successfully relating these changes to the degree of weathering of the cultural relic. This study developed a linear fitting method for systematically assessing the degree of weathering of stone cultural relic, which is a significant improvement over traditional assessment techniques. Our approach not only enhances the accuracy and applicability of Tv as an evaluation index but also integrates environmental temperature considerations, ensuring a more reliable assessment under varying conditions. The study's findings validate the effectiveness of infrared thermal imaging in identifying deterioration types and evaluating their severity, setting a new standard for the protection and restoration of stone cultural relics.