Abstract Numerical bed change study of Danau Diatas and Danau Dibawah was conducted. Hydrodynamic and sedimentation simulations are carried out using monthly discharge input limit conditions obtained from the calculation using the FJ Mock method. The RMA2 numerical model is used to obtain current patterns that are calibrated against the measurement results. Estimated land erosion is calculated using the USLE equation. Sediment discharge obtained from the USLE equation is used as an input of sediment sources to obtain sedimentation patterns using the SED2D module. The results of the modeling of the current pattern get the current velocity ranging from 0 - 0.05 m / s for Danau Diatas and between 0 - 0.04 m / s for Danau Dibawah. The bottom profile change due to the distribution of sedimentation was found to range between 0.12 ∼ 0.21 m in one year simulation with a radius of 0,53 and 1,72 km. This study is a preliminary study to get an idea of the potential for sedimentation. The validity of the results is recommended to use bathymetry measurements to see the bed changes that occur with the time of measurement. The initial description obtained has shown the need for efforts to regulate land use and commensurate with lakes in anticipation of silting of lake waters due to erosion.