This thesis is part of a larger ongoing study of the vegetation of Benishangul Gumuz National Regional State. Wetlands are a little studied part of this vegetation, and have not been subject to ecological analysis before. This study aims to analyse the vegetation community structure of a wetland near Assosa, the capital of the region. The study was conducted over the first three days of October 2005, at the end of the rainy season in western Ethiopia. The site consisted of a tall grass and sedge dominated wetland surrounded by mixed broadleaf woodland and thickets of Oxytenanthera abyssinica. A total of 29 4m2 plots were analysed for species abundance, and soil was collected for chemical analysis and seed bank experiments. TWINSPAN and DCA analysis of the species abundance data and correlation tests with soil variables led to the conclusion that two main ‘community types’ were present in the wetland: The Scleria community at the wetter core of the wetland and the Aneilema community in the margins and drier parts of the wetland. The main environmental gradient governing species composition was hypothesised to be a gradient in wetness, in part determined by distance to the water table.The seed bank was investigated using the emergence method. The seedlings that germinated from each sample were counted and identified. A total of 28 species in 13 families were found, and the average number of seeds/kg of soil was 49.5. There was a 1:1 ratio of annual to perennial species and of species of wet and dry habitats. Many of the species germinated were weedy species and this element of the vegetation could increase if the wetland is subject to disturbance.