This book constitutes the refereed proceedings of the 15th China Conference on Wireless Sensor Networks, CWSN 2021 held in Guilin, China, in October 2021.The 19 papers were carefully reviewed and selected from 60 submissions. The papers are organized in topical sections on ​theory and technology on wireless sensor network; application on internet of things; security and privacy protection on internet of things; fog computing and wireless computing.