Excessive　information　on　traffic　signs　prevents　drivers　from　having　time　to　read　and　comprehend,　leading　to　high-risk　driving　behavior.　In　this　paper,　a　dynamic　visual　cognition　test　in　the　driving　simulation　barn　was　conducted　to　measure　the　driver＇s　change　of　behavior　during　their　recognition　of　traffic　signs　with　various　numbers　of　road　names.　Three　indexes　were　obtained,　including　visual　cognition　time,　vehicle　acceleration,　and　the　offset　distance　from　middle　lane　under　different　driving　speeds.　Data　analyses　indicated　that　three　indexes　would　increase　as　the　information　volume　increased.　The　high　driving　speed　would　make　driver＇s　visual　cognition　time　decrease　and　traveling　state　more　unstable.　So　the　excessive　information　has　a　significant　influence　on　driving　behavior　and　it　would　affect　driving　security.　The　findings　are　useful　for　future　traffic　sign　design　and　safe　driving　behavior　research.　©　2011　ASCE.