Potential erosion value of the Gam river basin is calculated based on universal soil loss model (USLE) of Wischmeier and Schmid. The results for the potential erosion across the entire basin and level 2 basins by 5 levels of potential erosion show: the area of potential erosion at very low level and low level accounted for 63.7 percent, at high level and very high level accounted for 16.6 percent of the total area of the basin. Between the river basins level 2 is quite clear differentiation of the level of potential erosion, in which, river basin level 2, river basin level 4 and river basin level 3 have the highest soil erosion risk.