Riverine vegetation along the Awash River between altitudinal gradient extending fromrn350-1470 m a.s.1. was studied to describe major plant communities and relationshipsrnbetween plant communities, edaphic, climatic and topographic factors. Ethnobotanicalrninformation was gathered from key informants and the plants were described briefly.rnTwo field trips were conducted in December 1999-Januaiy 2000 to the Awash basin inrnthe East Shoa Zone of Oromia Regional State and the Afar Region. A total of 65 relevesrnWere analysed . in each of the sample plots the floristic composition was qualititativeiy analysed systematically within a nested belt transect of 100in laio parallel to the tivet cover/ abundance value was estimated for each species basec on braun banquet ampproach all woody in dviduais taller than2 mand thicker than 2 cm were mcasured for height and diameter at breast height (dbh)environment vartaies measuied inciude Altitude, Slope, Soil Texture, Sand %, Silt % and Clay %, pH, Cation ExchangernCapacity (CEC), Electrical Conductivity (EC), Organic Carbon (OC), available Sodiumrn(Na), Calcium (Ca), Potassium (K), Magnesium (Mg) and base saturation. Sevenrnvegetation communities were described. Acacia nilotica subsp. leiocmpa (L.) Wil/d. ex.rnDel.-Carissa edldis Vahl. type; Acacia robllsta Burch. subsp. lIsambarensis (Taub)rnBrenan,-Acokamhera schimperi (A. DC.) Schweinf. type; Celtis ajricana-Mimllsopsrnlallrijolia type; Acacia senegal-Acacia lIlellijera-DoberQ glabra type, Acacia Ililoticarnsubsp. indica-Ficus capreaejolia type, Lannea schimperi-Glycine lVightii type andrnTalllarix nilotica-;Acacia hocki community type. 36 plant species were described asrnethnobotanically significant plants as informed by key informants. All plant specimensrncollected were identified and deposited in the National Herbarium (ETH.).