This book constitutes the refereed proceedings of the 23rd International Conference on Artificial Intelligence in Medicine, AIME 2025, which took place in Pavia, Italy, during June 23-26, 2025. The 49 full papers and 81 short papers included in the proceedings were carefully reviewed and selected from 311 submissions. They deal with the development of theory, methods, systems, and applications of AI in biomedicine, including the application of AI approaches in biomedical informatics, healthcare organization, and molecular medicine.