In order to effectively develop the autonomous vehicle, this paper studies the development situation and key technology of autonomous vehicles. We introduced the related concepts of autonomous ground vehicle and their advantages and disadvantages. We also offered the details about the research and development of autonomous vehicles in the world and analyzed the structure and composition of autonomous vehicles. What’s more, we described the five key technology modules: environmental perception, positioning navigation, planning decision-making, control systems and traffic simulation. At last, we point out the future development of autonomous vehicles and the way for us to go forward.