This book constitutes the refereed post-conference proceedings of the Third International Conference on Applied Intelligence and Informatics, AII 2023, held in Dubai, United Arab Emirates, during October 29-31, 2023. The 31 full papers included in these proceedings were carefully reviewed and selected from 99 submissions. They are organized in these topical sections as follows: Emerging Applications of AI and Informatics; Application of AI and Informatics in Healthcare; Application of AI and Informatics in Pattern Recognition; Application of AI and Informatics in Network, Security, and Analytics.