长城已被列为濒危的世界文化遗产之一。由于长城分布的于线很长，调查困难，致使长城家底不清，保护管理工作很难进行。本文提出一种从遥感影像上快速提取长城的方法。本文选取了典型砖石结构的八达岭段长城，利用SPOT5遥感数据，对其进行NDVI处理，初步提取“类长城地物”；再利用1：10000DEM数据提取山脊线建立缓冲区，将两者进行叠合提取长城，再通过形状指数法去除多余图斑，得到最终结果。应用上述技术路线提取出的八达岭长城与已有资料进行比对提取精度较高。

The Great Wall has been in the severe danger of the World Culture Heritages list. it is difficult to investigate the situation, because the Great Wall stretches too long and we do not know the exact layout of the Great Wall. The protection and management of the Great Wall is a hard work. In this paper, there is a new method to extract the information of the Great Wall from the satellite images. The research area BaDaLing is one of the typical stone Great Wall. Firstly we obtain the NDVI value from a SPOT5 image after fusion and orthorectification. Then use the DEM hydrology function to extract the ridge of the watershed, and buffer it. At last we put the NDVI and the buffered data together to make an overlay, then the Great Wall information is extracted. We apply the shape index to the overlay to get rid of other spots. The result is confirmed through the field survey. The method can provide reference to the Great Wall survey.