The　driving　environment　is　relatively　narrow　at　the　tunnel　portal,　where　the　driver　would　feel　depressive.　At　the　same　time,　a　sharp　rise　in　luminance　at　the　tunnel　portal　will　impede　the　driver＇　vision.　So　countries　are　using　artificial　lighting　to　improve　the　driving　environment.　However,　artificial　lighting　with　inappropriate　application　engenders　a　feeling　of　discomfort,　even　resulting　in　visual　impairment　and　other　hidden　dangers　in　driving　comfort　and　safety.　When　the　luminance　difference　between　inside　and　outside　the　tunnel　during　daytime　or　at　night　is　large　enough,　a　＂White　Hole＂　phenomenon　would　occur　visually.　Until　now,　all　countries　using　luminance　index　to　design　and　appraise　the　tunnel　lighting.　From　the　experiments　of　recognition　on　human　eyes＇　dynamic　adaptation　from　darkness　to　brightness,　this　paper　established　evaluation　indexes　for　the　light　environment　of　the　tunnel　entrance　at　night,　which　are　color　temperature　and　luminance　difference.　Furthermore,　this　paper　obtained　the　function　of　recognition　distance,　color　temperature,　and　luminance　difference　under　different　driving　speed,　from　which　we　could　get　the　tunnel　lighting　criteria　and　controlling　strategy.　Methods　and　conclusions　in　this　research　could　help　understand　and　eliminate　the　＂White　Hole＂　phenomenon　better,　and　provide　support　in　designing,　monitoring,　and　operating　the　light　environment　of　tunnels.　©　2018　American　Society　of　Civil　Engineers.