Limited varieties are among the major factors that limit cassava production in Ethiopia. Therefore, afield experiment was conducted in the Mela and Bodisub-districts of Gena Bosa district in Dawro Zone during 2017 cropping seasons, to determine the growth response of cassava varieties. The treatments consisted of four varieties (Local, Variety, Kello and Awassa-04 varieties) and two locations (Mela and Bodi sub-district). The experiment was laid out as a randomized complete block design (RCBD) and replicated three times per treatment. Data were collected on phenology, growth, yield components and yield. The data were subjected to analysis of variance. The results indicated that interaction effect of variety and locations were significantly affected crop phenology, growth, yield components and yield. Awassa-04 variety planted both at Mela and Bodisub-district significantly improved phenology, growth, root morphology, yield components, and root yield of cassava. The average root yield of cassava obtained in Awassa-04 variety planted at Mela sub-district about 46.5% exceeded the average root yield obtained from local cassava planted at Bodi sub-districts. The highest mean net benefit (162,880 ETBha^–1) with an acceptable marginal rate of return of 3,460% was obtained fromAwassa-04 variety. Thus, planting Awassa-04 variety is suggested for maximize the agronomic and economic returns of cassava farmers in the study area.