The　characteristics　of　driver　workload　are　researched　in　order　to　reduce　driving　risks　in　long　highway　tunnel.　Based　on　experiments,　by　analyzing　the　characteristic　law　of　drivers＇driving　workload　in　Qinling-Zhongnanshan　tunnel　which　is　the　longest　highway　tunnel　in　China　so　far,　we　give　the　conclusions　as　follows:　the　driving　workload　at　the　entrance　and　exit　is　higher　than　outside;　the　driving　workload　inside　the　tunnel　is　lower　than　outside,　and　the　driving　workload　decreases　with　the　time　prolongation;　changing　the　drab　inner　surroundings,　such　as　the　special　lighting,　can　increase　driving　workload,　but　the　effect　of　multiple　same　view　on　improving　drab　inner　surroundings　weaken　gradually.