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Tanralili Sub-Watershed is the upstream of the Maros watershed which experiences land problems in the form of erosion and sedimentation. The Tanralili Sub-Watershed is a water catchment area that serve as a source of clean water for the Eastern and Northern regions of Makassar. This Sub-Watershed continously experience land use changes in sedimentation rate and as a result decrease the water discharge of the Lekopancing Dam (downstream of the Tanralili Sub-Watershed) from 1000 liters/second to 200 liters/second. Therefore, research related to sedimentation rates in the Tanralili Sub-Watershed is needed to obtain information on the sedimentation rate that occurs. This study used SWAT (Soil and Water Assessment Tools), a hydrological modeling that calculates sedimentation rates. SWAT procedures are divided into 4 processes, namely delineation, generation of Hydrological Response Unit (HRU), data processing and model simulation. For the procedures, the data input are slope condition, soil type, land cover, and rainfall intensity. The results showed that the accumulation of sediment for 10 years in the Tanralili Sub-Watershed reach 7,618.85 tons/ha/year from 41 Sub-Sub-Watersheds. The highest sediment rate occurs in Sub-Sub-Watersheds number 26, 27, and 38 which are dominated by dryland agricultural land cover and rice fields located on slopes of 25-45%. Meanwhile, the smallest sediment rate occurs in Sub-Sub-Watershed 9 which is dominated by forest land cover which is on a slope of 15-25%.