Aiming at the poor automation in monitoring the environment of chicken coops in rural areas， an IoT monitoring system for chicken coops based on LoRa technology was proposed and developed. The focus is on designing sensor nodes and gateway nodes in the perception layer. The STM32 microcontroller and LoRa module are the core of sensor nodes. According to the monitoring technical indicators specified in the local standards for monitoring the breeding environment of broilers and laying hens， the hardware circuit of the sensor nodes was designed by selecting the temperature and humidity sensor module， the light intensity sensor module， and the ammonia sensor module. The sensor node monitors the environmental parameter information of the chicken coops in real-time and sends the data to the gateway node through LoRa wireless communication technology. After receiving environmental data， the gateway node sends the data to the WiFi router through the ESP8266 communication module. Then， the data is transmitted to the cloud platform OneNET for processing. The test results indicate that stable wireless transmission of data can still be achieved when the distance is 800 meters. The system not only meets the environmental monitoring requirements of large-scale chicken coops， but also provides an effective implementation plan for environmental monitoring of agricultural livestock and poultry breeding.