Sediment transport is a global environmental problem that degrades soil productivity, water quality, causes sedimentation of reservoirs and increases the probability of floods. The Gefersa reservoir, one of the sources of surface water supply for the city of Addis Ababa for the past 70 years, has faced several problems. The reservoir supplies an average of 30,000m3per day with a storage capacity of 6,500,000m3. This study was conducted in the upper catchment of the Gefersa reservoirwith the objectives of estimating reservoir sedimentation and specific sediment yield of the Gefersa reservoir using the RUSLE model integrated with the GIS environment. The research put together the Revised Universal Soil Loss Equation (RUSLE) model to identify the soil erosion hotspot areas. The findings show that the annual soil loss rate of the upper catchment is about596tons/ha/yr. The study indicated that the sediment yield and specific sediment yield are 0.36 and 214ton/ha/yr respectively. From the results of this study, the researcher concludes that the soil loss from the upper catchment of the reservoir is small which is below the limit as stated by FAO. This is due to the well-conserved catchment and the existence of Gefersadam (III) for sediment trap at upstream of main Gefersa dam (I/II)to prevent the dam from sediment deposition. Albeit that soil erosion is, less it is important to quantify the soil loss at the catchment level to recommend additional sediment trapping techniques for the dam safety.