With the rapid development of the prepared dish industry, the problem of remote monitoring and management of its refrigerated environment has become increasingly serious. Traditional RS485 and ZigBee have problems such as complicated cabling and long transmission distance in multi-node networking monitoring scenarios. This study designed a set of Internet of Things monitoring terminal based on Lora technology, the core controller of the system uses STM32F429 chip, node and gateway data transmission equipment uses lora transmission module, combined with sensors to collect the working parameters of cold storage equipment. The star AD hoc network is constructed with lora module, and the data of the terminal node is transmitted to the gateway in the way of host polling and displayed visually. The temperature and humidity, ambient temperature and working current of the prefabricated vegetable refrigerating equipment were tested. The effective communication distance of lora in complex and open environment is tested. The results showed that the communication distance of lora in complex environment is 300m, and it can reach 500m in open environment. The system is stable and reliable, and can meet the needs of data monitoring of prefabricated vegetable refrigeration equipment.