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The main factor causing the decline in water storage capacity of civil infrastructures especially reservoirs in Indonesia is the high rate of sedimentation. Land degradation by erosion in the reservoir catchment area is contributed to the high sedimentation. Mitigation on sedimentation problems can be carried out by estimating the erosion rate and sediment yields occurring as well as controlling erosion and sedimentation. This study aims to identify the rate of erosion and sedimentation that occurs in the Logung Reservoir catchment area and assess its countemeasures. RUSLE-GIS based grid model is applied to estimate the erosion. Several erosion and sedimentation countermeasure scenarios were analyzed to determine the significance level of erosion reduction and sedimentation that occurred. The results showed that the rate of erosion in the upstream watershed of Logung Reservoir was 803,823 m3 / year while the sediment rate was obtained at 177,568 m3 / year. Sediment countermeasure with land use arrangements provides more significant results than with the construction of check dams. Construction of check dam is only able to reduce sedimentation by around 22%. Land use arrangements can reduce sedimentation by 45%. While the combination of controls between the two methods can reduce up to 87%.