Abstract: In order to realize the automate management of agriculture, and the implementation of precision production and providing comprehension information for scientific research, the farm environmental monitoring system based on the Internet of Things (IoT) was designed, the system was made up of 3 layers which were sensor layer, transmission layer and application layer, respectively. The modular structure was adopted to develop coordinator node and routing node which had flexible structures and strong versatility, the node connects with sensors through standard analog interface, on the basis of which, high reliability, flexible Wireless Sensor Network (WSN) was built, the WSN could perceive environment information for greenhouse tomato growth in a read time way, and transmits the data to the remote server management system reliably. Field experiments showed that the farm environmental monitoring system based on the Internet of Things was stable and reliable and provided basis for the scientific forecasting and science cultivation.