Roads are a conspicuous component of the landscape and play a substantial role in defining landscape patterns.While previous studies have demonstrated the link between roads and their effects on ecological processes and landscape pattems,less understood is the landscape pattern imposed by different roads classes in relation to landscape factors such as human disturbance,road density and vegetation type,etc.Our study focused on the vegetation fragmentation in Xishuangbanna prefecture in Southwest China to elucidate the effects of road extension on different vegetation types.The results showed that the impacts on vegetation varied with road class.Low level roads affected the most vegetation patches.Cultivated types were influenced by the largest patch area and number in the road effect zone and forests with Cindica,Castanopsis hystrix A.DC and Schima wallichii were second.We also analyzed the landscape metrics of 145 quads and of the whole region with five road development scenarios.The results pointed out that minor roads including class IV and V roads contributed most to landscape fragmentation at different scales.Linear regression was used to exaqmine the relationship between road features,village distribution and environmental factors.The results showed that different road classes had a close relationship with village distribution,while topography fluctuation influenced the road and village pattern.Though strong relationships between landscape fragmentation and roads were found,topography had no direct relationship with vegetation landscape patterns.