This book constitutes the refereed proceedings of the 9th EAI International Conference on Smart Grid and Internet of Things, SGIoT 2025, held in Taichung, Taiwan, during December 6–7, 2025.

The 22 full papers included in this book were carefully reviewed and selected from 54 submissions. They are organized in the following topical sections: IoT, Artificial Intelligence, Edge Computing; Wireless Sensor Network, Mobile Robot, Smart Healthcare; and Protocol, Algorithm, Services and Applications.