This book constitutes the proceedings of the 4th International Conference on Internet of Vehicles, IOV 2017, held in Kanazawa, Japan, in November 2017.  The 19 papers presented in this volume were carefully reviewed and selected from 40 submissions. They deal with advances in the state of the art and practice of the IoV architectures, protocols, services and applications, as well as identifying emerging research topics and define the future directions of Internet of Vehicles. .