Abstract: More and more IoT (Internet of Things) systems have been deployed in a wide variety of applications, and they are influencing many aspects of our life. However, IoT applications are characterized by their strong domain specificity. This characteristic of IoT has brought new design requirements of the node. Firstly, IoT nodes must have strong versatility, and be able to adapt to a variety of applications. Secondly, IoT nodes need to have strong professional characteristic, and can be customized to fit well a specific application. To meet these requirements, we propose a reconfigurable node architecture for IoT based on the joint design of software and hardware, named EasiSHA. Specifically, we present a task scheduling mechanism, which can change dynamically the implementation of tasks based on the performance requirements. Thus, it can reduce redundancy of hardware and software, and also minimize overall power consumption. Furthermore, we propose a shield layer between applications and tasks to improve the reusability of software, and reduce the correlation of applications and tasks. Therefore, the development speed of applications is improved and system development costs are reduced. Based on EasiSHA, we have designed a node prototype and applied it to a number of actual applications. The verified results show that it can accelerate the speed of deployment of the IoT applications, and reduce R&D costs effectively.