This paper aims to propose an IOT(Internet of Things) gateway with multi-channel of RS485, which ensures the real-time performance and reliability for IOT while transferring data between the application and the underlying layer, improving the organization and management efficiency of endpoint devices and solving the problems of data transmission among different protocols. Based on STM32F107 and VK3224, the gateway extends the 32-way RS485 ports, making data interconversion and transmission between the RS-485 interface and Ethernet possible. It helps to uniformly monitor and manage many devices through Internet at the same time effectively and become stable during actual running.