As for the problems of inefficient monitoring for agricultural products storage or transport, an agricultural products monitoring system based on STM32F103VET6 MCU is designed. The temperature and humidity sensor DHT11 is used in this system to measure temperature and humidity value. The measured data can be displayed directly on the screen and the data can be sent to mobile phone APP, which is convenient for observers to check. In addition, the required temperature and humidity threshold value can be set for different storage environment through the buttons or the mobile phone APP communication. The beep will be triggered immediately when the real-time temperature and humidity exceeds the threshold value, After the system test, the results show that monitor can work in different conditions, which also can send every value accurately to users. the expected effect can be achieved completely, the system is able to as an accuracy, convenient and real-time monitor for storage environment of agricultural products, which is low cost and can be used widely.