Abstract:Road networks may greatly influence hydrologic and geomorphic processes in a watershed. The relationship between road distribution pattern and landuse type is crucial for the quantization of road network characteristics in a small watershed. This study was conducted to explore the manner in which landuse type affects road network distribution pattern. Road networks in different periods( 1982 and 2002) were extracted based on high resolution remote sensing images of Zhifanggou watershed in the central Loess Plateau. In turn, the road networks were overlaid with the landuse types in corresponding periods. GIS spatial analysis and statistic methods were used to study the correlation of road segment position and length with the changed landuse types. Results show that in a watershed, the changed landuse may influence road netw ork significantly. Nevertheless, roads in different levels receive different effects from changed landuse type. Roads of the third and forth levels are influenced more greatly than the second level roads. Linear function may be used to describe the relationship between the forth level road length and the area of land blocks. An equation optimized by the landuse type affection degree to human activity is proposed to get road length based on land block areas.