The two-volume set CCIS 2617 and 2618 constitutes the refereed post-conference proceedings of the 5th International Conference on Optimization, Learning Algorithms and Applications, OL2A 2025, held in Sesti Levante, Italy, during April 28–30, 2025.The 38 revised full papers presented in these proceedings were carefully reviewed and selected from 92 submissions. The papers are organized in the following topical sections:Part I: Optimization; Optimization in Control Systems Design; Artificial Intelligence in Healthcare and Medicine; and Deep Learning.Part II: Optimization in the SDG context; Machine Learning; and Machine Learning and Artificial Intelligence in Robotics.