The drunk driving monitoring system based on single-chip microcontroller has received widespread attention and research both domestically and internationally.It mainly integrates modules such as singlechip microcontroller, alcohol concentration sensor,A/D converter,and sound and light alarm to achieve real-time monitoring and over limit alarm of alcohol concentration in the driver's exhaled gas.At present,research focuses on high-precision alcohol sensors,data fusion technology,embedded system development,and system integration and intelligence.However,the stability and accuracy of the 51 series microcontrollers used in most systems need to be improved,and system power consumption,communication speed,and environmental adaptability need to be continuously improved.Based on the design requirements of system usability,reliability,and safety stability,the paper designs the drunk driving monitoring system based on STM32.The system is mainly developed and designed using an embedded system,including the functional design of hardware circuits and the debugging and verification of software programs.Specific design and functional analysis of each part of the system circuit are carried out to design the minimum application system that meets the requirements.The software adopts optimization programming methods to ensure smooth system operation.The overall design of this system is simplified,easy to operate,functionally optimized,and cost-effective.After debugging and testing,the system can accurately detect alcohol concentration with an effective rate of 96.5%and an error of no more than±5%,making it highly valuable for promotion and use.