This study analyzed the sustainahility of Tibila irrigation based integrated development projectrnloea/ed in Arsi Zone of Oromia region, Ethiopia. Results are based on primOly and seconc/Cl1y dalarncollected f rom a sample survey of 110 households, focus groups discussion and key informantrninterviews as Hlell as secondwJ' documenl analysis. Analysis in descriptive s/o/is/ieal methods usingrnSPSS, IBM is used and analysis of qualitative information supplemented the result. The project wasrnanalyzed against socio-economic, technical and environmental sus!cdnability 's. The scheme is a newrnlarge scale irrigation based development project under implementation and development. lJ wasrnplanned to cover about 7000ha of land when totally completed and will support a population morernthan 16000. Currently about 2000/emuers are using 1200ha of land to produce with. The results Ii/rnthe sludy revealed Ihal 'within the fhree year lim e, the farmers were producing 3-6 rounds and il isrnfo und fhal farm households have started 10 grow crops which were not previously grown in the areasrnsuch as passion fruits. It was also found (hat il has a positive hnpact on their ;'1come, on employmentrnimprovement as well as on the living standard oftheirfamilies. In addition, through time beneficiclIYrnfarm households depend more on the production ji-om their irrigated/ields, which enabled them tornharvest more than once a year. Therefore, as beneficiOlY farmers shift to high value but perishablerncommodities, emphasis should be given to market ;'1g extension, espedal/y infadhtaling markels andrnmarkel linkages to farmers. Furthermore, Through time Ihe demand for irrigation waler increasesrnamong benejiciclIY farmers. As a result, scarcity of water especially during the peak period isrnexperienced Some conflicts on waler use (mel distribution are also experienced among thernbenefiCiaries due 10 certain technical faulls, management challenges and some inefficiency's. Evenrnthough Environmental challenges such as sahnity, logging and erosion are al their inilial stage,rnemphasis should be given to water shed managemenl and improvedfarming land and in-;gation walerrnmanagement practices. Waler User Association or organization and farmers have /0 be strengthenedrnand empowered in depth in technical, i.e. water managemenl, fanning lechnologies, institutional andrnscheme adminiSlraiions and in environmental issues 10 use Ihe scheme on suslainable basis l llilernkeeping the socia-economic and ecological balances in the basin.rn(Key words: - Sustainability, Water management, socio-economic and ecological balancel