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.