Abstract: In order to measure driving fatigue effectively, electroencephalogram (EEG) coefficient of variation indicators are proposed, which reflect drivers arousal levels and fluctuations. The derivation of the indicators was introduced first, and then the validity of the indicators was studied through driving simulation experiment. Reaction times of breaking and subjective self-assessed indicators were taken as independent indicators. The changes of the independent indicators over time and the correlation coefficients between the EEG indicators and break reaction time were analyzed. The results show that the EEG coefficient of variation indicators θ_CV and β_CV are reliable, and there is a driver resistance stage when driving fatigue occurs.