提出一种基于DEM数据、适用于复杂地形区域的相对高程因子的计算方法。首先利用DEM数据划分地形单元，然后在每个地形单元内确定相对基准面，最后分区域计算相对高程。并选择河北省承德市丰宁县为研究区开展实验验证，研究表明，该方法能够方便、科学地计算出相对高程值，并为复杂地形区域相对高程提取及数字高程模型研究提供一种新的方法与借鉴。

In this paper, we proposed a calculation method for relative elevation factor based on DEM data, which was suitable for complex terrain regions. Firstly, we divided the terrain unit according to DEM data. Then, we determined the relative datum plane in each terrain unit. Finally, we calculated the relative elevation in different regions. We selected Fengning County, Chengde City, Hebei Province as the study area to carry out experimental verification. The research shows that this method can calculate relative elevation easily and scientific, and provide a new method for relative elevation extraction and reference for digital elevation model research in complex terrain regions.