To study the law of drivers’ eye movement indices,indoor simulation driving experiment method was adopted, two-lane second-class grassland highway was designed to simulate real road conditions. 48 subjects were selected for the experiment,groups were divided according to different driving ages, three eye movement sensitive indexes including fixation duration, pupil diameter and scan range were extracted, the variation rule of eye movement index of drivers with different experience under different landscape environment was quantified. It was found that the relationship between the landscape environments and eye movement index was U-shaped,the changes of eye movement indexes of drivers at different driving ages were different.The results showed that 4/km was the optimal threshold number of combined elements.In this environment, the change rate of driver eye movement index was the largest,extraction information was the most;When the number of elements was greater than or less than 4/km, the change rate of driver eye movement index would decrease. The results could provide reference for improving and optimizing the design of grassland highway landscape environment.