Abstract:  Natural plant communities in inland arid areas and the quality of life of local residents，regional ecological security and geo-environment are closely related. The Dunhuang Basin，located in the northwestern China，is world-famous for its natural oasis and cultural heritage and selected as the study area. The objective of this paper is to map the distribution of natural plant communities in the area. This not only can provide long-term monitoring data of changes for studying on vegetation and groundwater system，but also can provide data support for ecological restoration project in the area. Thus，the RapidEye satellite remote sensing data was used to carry out remote sensing mapping of plant communities. First，investigation routines of vegetation sampling were set out according to landforms maps 1∶250 000 and 1∶200 000 hydrological maps. In each field site，the vegetation species type and number，vegetation coverage，height，and frequency were recorded. Plants were recorded 31 species belonging to 16 families，and there are nine kinds of dominant plants：Tamarix ramosissima，Popolus euphratica，Phragmites australis，Alhagi sparsifolia，Nitraria tangutorum，Lycium ruthenicum Murr，Allium mongolicum，Aeluropus trin，Halostachys caspica. Then，combined with the landform and hydrological maps，a multi-source geological data type method was supported by transitional method in order to determine the natural plant communities. The remote sensing interpretation signs of plant communities were established. The dominant species nomenclature was used to divide communities’ classification system in the study area and its remote sensing mapping was completed. There are 8 categories single dominant species communities in the area，taking up 73.73% of total study area；11 categories dual dominant species，taking up 22.22% of total study area；12 categories multilayer structure，taking up 4.05% of total study area. Finally，the relationship was analyzed between plant communities and landforms and soil salinization. Single dominant species，two dominant species and multilayer structures are well correspond to the landscape units，but there are the crosses in the same landform units. The higher the degree of soil salinization，the simpler the community structure is and having extremely low vegetation coverage；the lower the degree of soil salinization，the more complex the community characteristics tend to be and having higher vegetation coverage.

Key words: the Dunhuang Basin, natural plant communities, RapidEye, inland arid regions