Abstract: Under background of“smart food”，a set of bulk grain container monitoring system with the core of STM32F407 was developed.The system relied on wireless sensor networks，and combined with some new technologies，such as low power consumption，multi-source information transmission，narrowband Internet of things，GPS/Beidou Positioning.The system used Lora communication technology to transmit and receive data，process data by distributed sensors at different nodes to remote monitoring center，and took DTU（data terminal Unit）as signal transmission medium in the cloud.The system could monitor temperature and humidity of bulk grain container in real time，and send data to remote monitoring terminal by DTU.The system was stable and reliable，which was suitable for the mode of combined transportation of railway and water，and effectively improves safety and automation level of grain circulation.