This paper introduces an ultrasonic ranging system based on the Internet of Things, which uses STM32F407ZGT6 as the main control chip, uses HC-SR 04 ultrasonic sensor for distance measurement, DHT 11 temperature and humidity sensor monitors the environmental temperature and humidity, and communicates with Ali Cloud Internet of Things platform through ESP8266 Wi-Fi module. The system design aims to provide a low-cost and efficient real-time monitoring and remote control of environmental data, which is suitable for intelligent home, industrial automation, environmental monitoring and other application scenarios.