This three-volume set CCIS 2827-2829 constitutes the refereed proceedings of the 17th International Joint Conference on Computational Intelligence, IJCCI 2025, held in Marbella, Spain, during October 22-24, 2025. The 36 full papers and 83 short papers included in these volumes were carefully reviewed and selected from 146 submissions. They are organized into the following topical sections: Part I: International Conference on Agentic and Generative Techniques in Intelligent Computational Systems; International Conference on Fuzzy Computation Theory and Applications.Part II: International Conference on Evolutionary Computation Theory and Applications.Part III: International Conference on Explainable AI for Neural and Symbolic Methods; International Conference on Neural Computation Theory and Applications.