This book constitutes the refereed proceedings of the 20th International Conference on Knowledge Management and Acquisition for Intelligent Systems, PKAW 2024, held in Kyoto, Japan, during November 18-19, 2024. The 15 full papers and 9 short papers presented in this volume were carefully reviewed and selected from 52 submissions. These papers demonstrate advanced research on machine learning, natural language processing, computer vision, and intelligent systems.