In recent years, rare plants on the earth have gradually disappeared, so it is urgent to inspect and protect their health. A rare tree monitoring system compatible with NB-IOT (Narrow Band Internet of Things) is designed based on the low-power data transmission technology of LoRa (Long Range Radio). The system takes stm32f103c8t6 as the core of the controller, collects information through temperature and humidity sensor, attitude sensor, infrared pyroelectric sensor and sound sensor, builds a server to store the information and data back to the server, uses the terminal to access the server, and reminds the operator when the amount of information exceeds a certain threshold, Finally, the real-time monitoring of rare trees in the field is realized.