Abstract: We detected the changes of roads in outdated vector map using updated RS image automatically and semi-automatically.The changes of roads in map can be described by two types: one is partial changed or diminished compared with updated RS image;the other is new.Based on the registration of RS images and road networks map,we detect the changes of the two types as follows: one is,based on old map road networks,partial changes or diminishes in roads are detceted on images automatically,buffer distance is defined and methods of multi-scale template matching and strategy of knowledge is developed in this process;the other is,based on RS images,new roads are extracted semi-automatically.The model of auto-initial-value LSB-Snake is developed to extract new added road for the purpose.Experiments indicate the methods can detect the changes of roads in outdated vector map effectively and automatically.