The　anti-glare　facilities　in　median　strips　are　designed　to　block　opposing　headlights　in　order　to　avoid　disability　glare,　but　a　large　amount　of　headlight　leakage　results　in　uncomfortable　glare,　to　the　point　that　drivers　can　barely　detect　dangerous　obstacles　or　road　conditions.　This　paper　aims　to　explore　the　glare　range　under　high-beam　headlights　on　drivers＇　visual　requirements.　Based　on　an　analysis　of　the　mechanism　of　headlight　glare,　this　paper　proposes　a　subjective　headlight　glare　scale,　and　classifies　glare　discomfort　into　two　categories:　interference　glare,　and　acceptability　glare.　Combining　the　scales,　24　drivers　and　a　standard　light-emitting　diode　automotive　headlamp　were　used　to　conduct　glare　effect　tests.　The　size　of　the　laboratory　that　closes　to　scotopic　vision　is　12　m　x　6　m.　The　illuminance　thresholds　of　disability　glare-interference　glare　(DGIG)　and　interference　glare-acceptability　glare　(IGAG),　along　with　the　spatial　distribution　of　each　glare　level,　were　collected　at　the　longitudinal　distances　of　3　m,　5　m,　7　m,　10　m,　and　12　m.　Meanwhile,　the　illuminance　threshold　and　the　spatial　distribution　of　each　glare　level　up　to　a　longitudinal　distance　of　120　m　were　calculated.　The　results　indicate　that　disability　glare　is　distributed　in　the　central　area,　while　interference　glare　and　acceptability　glare　are　distributed　from　the　center　to　the　margins.　At　the　same　longitudinal　distance,　the　vertical　illuminance　of　the　driver＇s　eye　under　the　same　glare　level　is　almost　equal.　In　the　range　of　a　longitudinal　distance　of　120　m,　the　spatial　distribution　of　each　glare　level　enlarges　with　each　increase　in　longitudinal　distance.　The　results　can　provide　scientific　evidence　for　calculating　the　reasonable　heights　of　anti-glare　facilities　for　expressways　with　different　alignments.