Abstract： In order to achieve safe and comfortable threshold zone light environment of tunnels, from the point of the driver’s visual function and requirement, a threshold zone light environment evaluation method was proprosed based on the driving safety of visual cognition. Taking the color temperature of 5 700 K， and the color rendering index of 70 threshold zone light environment as the research object, car drivers were chosen for visual cognition testing with different running speed, to get the drivers’ dynamic visual characteristics. The visual cognition distance was selected as the evaluation index of tunnel threshold zone safety visual cognition. The Matlab mathematical statistics software was applied to establish the logistic regression model of visual cognition distance and luminance reduction coefficient. Different design speed luminance reduction coefficients which could meet the demand of driving visual cognition, and slightly higher than the current specification values were obtained. The research method and conclusions is this paper can provide technical reference for actual tunnel environment setting, monitoring and operation management.