Abstract: This paper introduce the design of intelligent navigation obstacle avoidance car system based on single chip microcomputer STM32F103. The system consists of MCU, GPS positioning, electronic compass, Bluetooth and ultrasonic transmitter module. The differences between two kinds of heading angles measured by GPS positioning, Bluetooth and electronic compass module is used to change the driving direction of the trolley, and the ultrasonic module is used to measure the distance to avoid obstacle. Finally, realize the navigation and obstacle avoidance of the trolley. After experimentation, the system can achieve 1.8 m precision navigation.