A technology of two laser coexisting on one girder was proposed to detect noncontactly the road surface roughness with the highway.And a method of equal height swing laser scan ranging was also proposed to measure the sharp and depth of cross direction rutting of road surface.Based on the innovation,an intelligent test automobile of highway surface was developed,which is used to detect the properties of highway road surface such as roughness and rutting,large number of actual detected data being obtained.The results have high coherence comparing with that obtained by similar instrument,but have much higher efficiency and precision.