Abstract: Background and Objective: Barley (Hordeum vulgare L.) is one of the major cereal crops grown in Ethiopia and for millennia it has been supplying the basic necessities of life for many in the Ethiopian highlands. This study was aimed to evaluate barley varieties as affected by various plant population densities in the highlands of Southeastern Ethiopia. Materials and Methods: In order to evaluate the effects of plant population densities on the yield and yield components and related quality traits of barley varieties, a split plot experiment in the form of randomized complete block design with 3 replications was carried out. The main factor consisted of three barley varieties and the sub factor consisted of 6 levels of planting density. Results: The results showed that EH1493 and HB1307 varieties was higher yielder than HB42 variety. The highest grain yield of EH1493 and HB1307 varieties were recorded at 261 plants m–2 or control whereas the highest yield of HB42 was obtained at 500 plants m–2. The maximum values of 1000 grain weights of almost all three varieties were gained from 261 plants m–2. The highest values of hectoliter weight was gained from 300, 200 and 400 plants m–2 for EH1493, HB1307 and HB42 varieties, respectively. Conclusion: In short, it was concluded that based on grain yield and related yield components 261 plant m–2 was economically feasible for the production of EH1493 and HB1307 food barley varieties around Lemu-Bilbilo areas and similar agro-ecologies.