Satellite-rainfall products are recognized as an essential source of rainfall data, especially in thernregion where ground based measurements are unavailable. Therefore, the main objective of thisrnstudy is to Apply a Satellite based Rainfall-Runoff estimation: in Upper Omo-Gibe Basin tornsimulate the extreme flood event at Omorate and with specific objective of evaluate therncapabilities, applicability and limitations of satellite rainfall products such as CMORPH, TRMMrn3B42v7 and PERSIANN, and inputs of hydrological models to simulate the Rainfall-Runoff byrnhydrological model NAM and preparing the Flood Hazard map in the lower water shed usingrnMIKE-11,MIKE-21 and MIKE-FLOOD. These products and inputs were employed to simulaternstream flow in the Great Gibe Watershed. The study period 2000-2012 was used forrndownloading and extracting the selected satellite rainfall estimates with daily-temporal and 0.250rnx 0.250 spatial resolution.rnSensitivity and uncertainty analysis, calibration and validation of the model were done usingrnMIKE ZERO particularly the Sequential Uncertainty Fitting (SUFI-2) algorism for all rainfallrninputs independently. The calibration period was from 2001-2005 leaving one years as a-warm uprnperiod and the validation period was from 2006-2012 for satellite rainfall based simulations asrnwell as in situ based simulations. Based on the modeling results of Mike Zero models had showedrnbetter performance when calibrated with the in situ rainfall with model performance efficiency ofrnMean Absolute Error, Maximum Values and Standard Deviation models respectively while, thernsatellite rainfall estimates (TRMM-3B42v7 and CMORPH) showed relatively good performancernwhen calibrated on the models with Mean Absolute Error (5.21,4.24), Max.Val. (73.74,32.97) andrnStd. Deva.(7.46,4.24) in the case of Asendabo with relative to the ground based measurements inrnboth satellite based product respectively. But, PERSIANN satellite rainfall estimates showed poorrnperformance for all Mean Absolute Error (3.78), Max. Values (33.06) and Std. Deva. (4.24)rnbefore bias corrected.rnThe model output simulation results performance in analyzed of Rainfall-Runoff based up on therncoefficient of determination and Nash-Sutcliffe coefficient, during the calibration it is found to bern0.509 and 0.64 respectively and the total water balance error during calibration is 14.75%. Andrnduring validation period 0.645 and 0.675 respectively with the total water balance error is 17.5%.rnPeak and low flows between observed and simulated hydrograph were found matching well. Thernsimulated minimum and maximum runoff for 13 yearsâ€™ period the maximum annual runoff varies between 1466.3 mm to 7525.4 mm. The simulated runoff was maximum for the month of Augustrn(6977.4 m3/s) and minimum for the month of April (5540.6 m3/s). The single flood event of yearrn100 in the upper part of Gibe confluence flood plain simulated using MIKE FLOOD, whichrnintegrated the calibrated and validated 1D MIKE-11 hydrodynamic model with 2D hydrodynamicrnmodel MIKE-21 for the flood plain.