In order to quantify the relationship between the roadside landscape color of freeways and the α/β value of the driver's EEG signal,real vehicle experiments were conducted in Jilin-Hunchun freeway to collect the data.Based on the double exponential function,a relationship model between the landscape color and the α/β value of the driver's EEG signal was constructed.Then,by considering the cumulative impact of the driving time on the α/ β value,their relationship model is constructed based on the cubic Gaussian function.Finally,a model describing the relationships of the driving time and the landscape color to the α/β value was constructed by means of the joint modeling method.Model analysis results show that the landscape color is negatively correlated with the α/β value,i. e.with the increase in the brightness of the landscape color,the α/β value approaches to 1,which indicates a balance between the relaxed state and the alert state,and that there is a fluctuating relationship between the driving time and the α/β value,specifically,when a driver forces himself into an alert state,there is a game between fall- ing into fatigue and resisting fatigue.The findings can provide a theoretical basis for the landscape color design con- sidering the driving fatigue.