Abstract：Research on the relationship between vegetation and groundwater resources in arid and semi-arid regions is the foundation of groundwater evaluation, exploitation and management. With increasing emphasis placed on coordinative development of society, economy and eco-environment today, the relationship mentioned above has gradually become a hot research topic both in China and abroad. Based on the data concerning the spatial distribution of vegetation and the groundwater depth, the authors proposed a new semi-quantitative analytical method for large-scale ecological relationship between vegetation and groundwater, i.e., vegetation structure chart method, and carried out extensive applied research with the Ordos energy base as an example. By using vegetation structure chart method, not only the relationship between vegetation and groundwater but also the warning water level of vegetation succession caused by groundwater exploitation could be obtained. Besides, The developing trend of the vegetation succession can also be predicted. The vegetation structure chart method can be used to make a patterning analysis and research on the relationship between vegetation and groundwater on the regional scale in arid and semi-arid regions. The method is easy to operate, convenient to practice, and simple to implement in production and scientific research.