Abstract: Located at the southeast edge of the Qinghai-Tibet Plateau, the northwest plateau area of Sichuan Province played an important role in water conservation for the Yangtze river and the Yellow River basins. In this area, a variety of wetlands types were included such as herbaceous swamp, shrub swamp, swamp meadow, rivers and lakes, which played a crucial part in water conservation, flood storage, regulating climate, purifying water quality, maintaining biodiversity, and other important ecological functions. Based on the data accumulated in field survey of this region, a total of 34 families, 86 genera and 252 wetland species of vascular plants and 3 vegetation type groups, 7 vegetation types and 49 formations of wetland plant communities were reported in this paper. And the wetland seed flora had obvious temperate characteristics. These results were helpful for the research and conservation of biodiversity in this region.