This book constitutes the refereed proceedings of the 14th International Conference on Model and Data Engineering, MEDI 2025, held in Cairo, Egypt, during November 2&4, 2025. The 16 full papers and 17 short papers were carefully reviewed and selected from 72 submissions. The conference program for MEDI 2025 covered an extensive array of topics, such as data modeling, data management, ontologies, machine learning, model driven engineering, large language models engineering, federated learning, image processing, natural language processing, optimization, and advanced AI applications in healthcare and security.