The　rational　setting　length　of　the　driving　fatigue　arousal　section　in　a　tunnel　is　studied　to　reduce　the　driving　safety　risk　caused　by　driver　fatigue　in　a　tunnel′s　middle　section.　First,　consider　the　interaction　between　the　amount　of　stimulation　in　the　fatigue　arousal　section,　the　driver′　s　fatigue　arousal　degree,　and　the　driver′　s　fatigue　arousal　maintenance　time　after　fatigue　arousal　has　been　established.　Second,　static　arousal　tests　are　performed　using　45　test　scenarios　that　include　three　colors　(blue,　purple,　and　cyan),　three　brightnesses,　and　five　stimulation　durations.　The　law　of　arousal　degree　of　drivers　after　roused　in　fatigue　arousal　sections　with　different　stimulus　quantities　is　investigated,　and　a　correlation　model　between　stimulus　quantity　and　arousal　degree　is　established,　yielding　a　minimum　stimulation　quantity　setting　in　the　fatigue　arousal　section　of　no　less　than　8.84　cd·s/m2　.　Third,　the　arousal　maintenance　time　of　drivers　after　stimulation　in　the　arousal　section　with　different　stimulus　quantities　is　investigated,　and　a　correlation　model　between　stimulation　quantity　and　arousal　maintenance　time　under　various　operating　speeds　is　established.　Based　on　the　maximum　brightness　of　the　tunnel　fatigue　arousal　section　that　can　be　set　on　the　sidewall　at　different　speeds,　the　reasonable　length　of　the　fatigue　arousal　section　in　the　tunnel　at　different　speeds　is　obtained.　Finally,　when　the　design　speed　is　60,　80,　and　100　km/h,　the　lengths　of　the　driving　fatigue　arousal　section　at　x　(x　∈　[　1,　N-1])　are　160　m,　200　m,　and　220　m,　respectively;　the　lengths　of　the　last　driving　fatigue　arousal　section　should　meet　the　normal　driving　of　the　remaining　sections　and　should　not　be　less　than　65　m,　80　m,　and　90　m.　©　2022,　Editorial　Office　of　Tunnel　Construction.　All　rights　reserved.