A key trend in computing and networking is pushing processing and storage into the "cloud". However, the cloud computing paradigm is facing difficulties in supporting the delay-sensitive applications and improving the scalability for exploding connected devices. Moreover, most IoT devices are small and designed to operate with minimal resources, and these resource-constrained devices have little or no capability to defend themselves against sophisticated security attacks. Those challenges lead to the new paradigm “edge computing” which makes the cloud descend to the edge. This emphasizes leveraging the power of local computing and using different types of edge devices to provide better services. In this talk, we will explore the use of edge computing for 5G and IoT. Specifically, we will provide the efficient design of edge computing-enabled heterogeneous networks and the framework of leveraging edge computing for IoT security.