Soil erosion caused by natural or anthropogenic factors represents a widespread problem with a range of negative environmental consequences. Various measures and works are being carried out to mitigate and prevent the direct and indirect effects of erosion. These actions often cannot be implemented in a whole region prone to erosion due to limited financial or human resources. Therefore, identifying the area that requires particular attention for conservation is necessary. The objective of this paper was to determine the most vulnerable areas (sub-watersheds) to soil erosion in the Topčiderska River Watershed, located in northern Serbia, using available data: land use, soil characteristics, and mean watershed slope. Using such multi-criteria decision analysis methods as analytic hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS), the most vulnerable sub-watersheds were determined for three different scenarios. The results show a strong correlation between the ranking based on AHP method and TOPSIS method. It is observed that the most vulnerable sub-watersheds are characterized by the significant presence of arable land and very steep slope and thus have priority for conservation.