In　this　paper　the　great　influence　of　speed　limits　on　operation　efficiency　is　studied　through　the　establishment　of　a　model.　During　the　model　building　process,　operation　efficiency　is　measured　by　total　delay　of　system.　So　the　first　step　is　to　build　the　speed　limits-　operating　speed　model　with　the　help　of　statistical　software　SPSS,　and　the　model　is　Generalized　Linear;　then,　build　the　model　of　relationship　between　delay　and　operating　speed;　at　last　take　the　operating　speed-speed　limits　model　into　delay-operating　speed　model,　build　the　final　model　on　delay　and　speed　limits.　The　purpose　of　this　paper　is　to　rely　on　existing　resources　and　detailed　data,　and　exploring　safe,　effective　and　reasonable　speed　limits.　©　2010　ASCE.