The two-volume set LNCS 16046-16047 constitutes the proceedings of the 36th International Conference on Database and Expert Systems Applications, DEXA 2025, held in Bangkok, Thailand, in August 25–27, 2025. The 35 full and 22 short papers presented in this set together with 3 invited talks were carefully reviewed and selected from 123 submissions. They were organized in topical sections as follows: Part I: Industrial Keynote; Invited Talks; Large Language Models; Data Quality; Machine Learning /Artificial Intelligence Applications; Classification Techniques. Part II: Image Processing, Analytics, and Vision Systems; Recommender Techniques; Data Integration; Optimisation Methods; Graph Applications; Analytics; Security/Privacy; Benchmarks and Surveys.