The study was conducted in the islands of Lake Ziway located in the Main Ethiopian Rift partrnof the Ethiopian Rift Valley in south-central Ethiopia, The main objective of the study was torninvestigate the diversity, regeneration status, socio-economic importance and the factors thatrncause degradation of the plant resources in the islands, Vegetation and socio-economic datarnwere collected between 18 September and 7 November 2003, A total of 73 releves, measuringrn20 m x 20 m (400 /1/), l'ere established along line transects laid ,/i'om central part of eachrnisland to the lake edge in eight aspects, Herbaceous species were sampled by using a 2 m x 2rnm (4 m2rn) sub-releve laid within each relet'!!, In each relev!!, the cover/abundance of eachrnspecies was estimated, 1'oody species were counted, diameter at breast height of trees andrnshrubs and environmental variables (altitude, slope, aspect and position) were measured,rnParticipat01J' Rural Appraisal method was employed to generate the socio-economicrninformation, A total of 141 species belonging to 113 genera and 55 families were identified, ofrnwhich 18.4% were trees, 21,3% trees/shrubs, ]2,1% shrubs, 3,5% lianas, 4,3% herbaceousrnclimbers and 40.4% herbs, The overall diversity and evenness of woody species in the islandsrnwere 2,60 and 0,62, respectively, The number of species on the islands correlated withrnisland's size, degree of human disturbance as well as habitat diversity. The similarity inrnspecies composition betlreen the islands was loll', indicating that each island has its ownrnunique flora, Nine plant communities were recognized and described. The total density andrnbasal area of the vegetation were 2979 individuals ha" and 191 n//w", respective~l', Thernimportance value index and the diameter class distribution revealed that some species arernthreatened and need the highest priority for conservation, The socio-economic survey showedrnthat the island communities are high~)' dependent on the natural vegetation for various