Aiming at decreasing the risk of brake thermal fading, friction material failure and punc-ture caused by the high temperature of semi-trailer brakes, a driver-assisted wireless monitoring system for multi-brake temperature based on STM32 micro-controller was developed. As the main chip of sys-tem, MCU STM32 carry out data transceiver and conversion rules. Through the analysis and comparison of different temperature principle, the thermocouple temperature sensor was selected. Millivolt level voltage signal outputted by sensors was converted into a digital signal through the amplification, denoising, tem-perature compensation and AD conversion of the MAX6675 thermocouple temperature measurement con-version chip. Digital signal was sent to the the receiver master chip and the display through E61-TTL-50 wireless module, then the system will follow the set rules to complete the high temperature state classi-fication warning. Furthermore,an experiment was conducted and the results showed that the system tem-perature deviation was 0. 7% and the accuracy of system was high.