This book constitutes the refereed proceedings of the 15th International Joint Conference on Knowledge Discovery, Knowledge Engineering and Knowledge Management, IC3K 2023, held in Rome, Italy, during November 13-15, 2023. The 9 full papers and 8 short papers included in this book were carefully reviewed and selected from 166 submissions. They were organized in topical sections as follows: knowledge discovery and information retrieval; knowledge engineering and ontology development; knowledge management and information systems.