‘‘Tella’’ is one of the Ethiopian traditional beverages prepared by mother’s traditional way of fermentation from different ingredients and using different recipe. It is the most commonly consumed alcoholic beverage. However, the chemical and nutritional properties of this popular beverage was not optimized and fulfillment adequately. Also there is no standard procedure and standard range of quality parameters for tella production. In this case tella quality affect by mixing ratio hop to malt, fermentation temperature and fermentation time. Thus the main objective of this study was to investigate the optimization of fermentation process parameters (fermentation temperature, fermentation time and mixing ratio of substrates) during tella production from barley and wheat malt. In this study it was found that tella from barley and wheat malt pH, ethanol level, titratable acid, crude protein, carbohydrate and sensorial acceptability were analysed to investigate the effect of the three process variables. The state ease design expert 12 software and central composite design (CCD) under response surface methodology were used to determine the influence of mixing ratio hop to malt, fermentation time and fermentation temperature on responses. This study deals with experimental design consisted mixing ratio hop (50, 100, 175, 250 and 300 g) to 100 g malt, fermentation temperature 16, 20, 26, 32, 36ºC and fermentation time 2, 4, 6, 8 and 9 days with a CCD consisting of 20 experimental runs. Based on the result of this study the optimum and high tella quality obtained at 6 days fermentation time, 26ºC fermentation temperature with mixing ratio hop 175 g to 100 g malt. The optimal values finding in this study pH 4.49, ethanol level 6.35, titratable acid 0.92, crude protein 0.32, carbohydrate 2.27 and sensorial acceptability 4.36 obtained tella from barley. The optimal values from wheat malt were pH 4.56, ethanol level 7.16, titratable acid 0.95, crude protein 0.36, carbohydrate 2.18 and sensorial acceptability 4.65. Methanol and crude fat of tella from both malts not detected. When pH and ethanol level of tella from barley and wheat malt compared with standard requirement of beer, the optimized tella from both malt meet (ECS 52). But other parameters have not standard range for weather tella or beer due to this, the result of titratable acid, crude protein, carbohydrate and sensorial acceptability of tella were compared with literatures and those parameters were closed or tolerate with literatures. This implies the study decrease hazard chemicals methanol; maximize ethanol, pH and also find optimum process variables for nutritional values tella. Keywords: barley, wheat, RSM, CCD, Optimum, malt, Hop, Characterization