The design elements of the interface for augmented reality head-up displays (AR-HUD) (display area, layout, color) are key factors affecting the cognitive load of drivers. This study aims to analyze the impact of different interface design elements on driver cognitive performance, explore the optimal combination of interface parameters, and propose design optimization suggestions to reduce cognitive load and enhance driving safety. Methods: Eye-tracking was used in conjunction to test participants cognitive performance in a simulated driving environment. Conclusion: The study found that color and layout are critical factors influencing cognitive load, with the optimal parameter combination reducing initial gaze time to 0.826 s. Moreover, the interaction between color and layout has the most significant impact on cognitive load during driving. The findings provide important evidence for optimizing AR-HUD interfaces.