Abstract:The method for extraction of valley shoulder line and slope heel line is based on the shape features of valley shoulder line and slope heel line. Valley shoulder line is the boundary of upland and valley and is located on convex slope. Slope heel line is the boundary of valley slope and valley bottom and is located on convex slope. Both of them are characterized by the biggestlocal change in slope degree. Using these features in extraction,the method can provide sound flexibility and has high accuracy and high efficiency.