[Objective] A soil and water loss survey was conducted. The necessary data, the maps, and other relevant data were obtained to provide comprehensive support for water and soil conservation plans at county scale.[Methods] Based on the small watershed division in Baiquan County, Qiqihar City, Heilongjiang Province, a comparative analysis was used for soil loss mapping using the indices of soil erosion severity, soil erosion intensity, and the proportions of soil and water loss areas.[Results] Mapping based on the index of the soil erosion severity of a small watershed had obvious comparative advantages. ① The map can comprehensively reflect the area, intensity, and distribution of soil and water loss in the county. These can be implemented quantitatively and accurately to the water erosion unit—the small watershed. ② Based on this map, the distribution map of key prevention and control areas of soil and water loss, soil and water loss prevention, and the control layout map and major projects distribution map can be created directly. ③ The map, combined with the soil erosion intensity map of small watersheds, can provide necessary data for typical measure designs and configurations on a small watershed scale. Those data can be implemented to every plot.[Conclusion] From the perspective of carrying out a soil and water loss survey, delimitation of key prevention and control areas of soil and water loss, and comprehensively supporting the whole process of soil and water conservation planning, the county scale soil erosion mapping based on the index of the soil erosion severity of a small watershed has better comparative advantages.