Abstract: Through a set of dual-task rapid presentation sequence experiments, the effects of the visual complexity and spatial frequency of the car interface icons on the efficiency of visual search are investigated. The results show that the visual search efficiency is significantly interfered by visual complexity and spatial frequency, the recognition accuracy rate of low-complexity and high-spatial frequency vehicle interface icons is higher and the response time is shorter. The interaction effect between visual complexity and spatial frequency is very significant. This study shows that the visual complexity of automobile interface icons determines the visual processing mechanism of the subjects, and the icons tend to be processed as a whole when they are simple; high-spatial frequency information is the key dimension of car interface icon recognition, and the recognition of more complex icons requires the participation of high spatial frequency information; low-spatial frequency information is an factor affecting the familiarity of car interface icons. The results of this paper provide an important ergonomic basis for the icon design of the smart car interface.