The aim of the research was to determine how changes in the management of agricultural land (cultivation techniques, fertilisation, type of crop and crop rotation) influence on the leaching of nitrogen from the soil profile. Research was conducted in the Drava River plain in Slovenia. The impact of 31 different scenarios of potential change in agricultural land management was evaluated using the Soil and Water Assessment Tool (SWAT) model. The research was located on the shallow aquifer with alluvial bedrock composite from carbonate and silicate layers, which is the main source of drinking water in the area. The results of the SWAT model version 2009 showed that with the constant climate and land management technology, the magnitude of nitrogen leaching from the soil profile is mainly influenced by soil properties. The most drastic effect on the increase of nitrogen leaching showed vegetable production technology, followed by cereals (corn, wheat and barley). Vegetable production even in ecological production by Slovenian standards can result in similar leaching potential as conventional farming, due to unfavourable conditions originating from soil properties (shallow soil profile). Effects of grassland production may lead to 76-98% reduction in nitrogen loss from soil profile in comparison to current practices.