Sediments induced from the erosion of watersheds, in addition to soil loss and decline in soil fertility, causes the reduction of water quality and endangers the effective life of reservoirs due to sedimentation and managements. So, Estimation of sediment yield of streams is very important for water resources projects planning. So, to use of measurement data or empirical equals need to smaller data of stream and flow. However, sediment transport equations do not agree with each other and require detailed data on the flow and sediment characteristics. Aiming to prediction effect of land uses on soil erosion and sediment yield under various conditions of litho logy and vegetation, using Ilwis system. This study was performed in the Tange Gazi Watershed, a 832 square kilometer catchment, located in the Chahar Mahal and Bakhtiari, Iran. So, with three replications sampling for each homogonous unit, overall 200 samples were resulted and also Required data were provided by field study and Digital images processing. Results of current study shown that the most of the irreversible soil losses and sediment yield by USLE model occurred in the pastures and natural shrubs land uses that located on earthen mountain land units of study watershed. In these land uses, the effect of slope and overgrazing cause to increase of sediment yield in the spring season.