Driver　fatigue　is　one　of　the　main　causes　for　traffic　accidents.　It　is　very　important　to　identify　fatigued　driving　to　prevent　traffic　incidents　objectively　and　accurately.　Detecting　drivers＇　physiological　signals　is　an　important　method　of　identifying　fatigued　driving.　Moreover,　special　attention　has　been　paid　to　physiological　signals　as　methods　for　detecting　fatigues　driving,　such　as　with　ECG　(electroencephalography)　and　EEG　(electrocardiogram)　tests.　In　this　paper,　ECG　and　EEG　data　were　collected　through　experiments　conducted　through　a　driving　simulator.　The　ECG　trend　was　obtained　based　on　statistical　analysis.　Moreover,　we　compared　EEG　signals　under　the　awake　and　fatigued　states　by　combining　the　video　and　the　ECG　trend.　The　EEG　characteristics　were　then　extracted,　and　the　EEG　threshold　value　is　obtained.　The　effectiveness　of　these　indices　is　evaluated　in　further　experiments.　The　results　could　be　used　as　the　foundation　for　future　studies　on　driver　fatigue.　©　2011　ASCE.