This book constitutes the refereed proceedings of the 18th International Conference on Green, Pervasive, and Cloud Computing, GPC 2023, held in Harbin, China, during September 23-24, 2023. The 38 full papers and 1 short paper included in this book were carefully reviewed and selected from 111 submissions. They were organized in topical sections as follows: Industrial Digitization and Applications, Edge Intelligence, Mobile Sensing and Computing, Cyber-Physical-Social Systems, Pervasive and Green Computing and Wireless and Ubiquitous Networking.