Due to population growth and increased food needs, agriculture is making an important contribution to greenhouse gas (GHG) emissions and thus to climate change. The paper analyzes the sources of GHG emissions in agriculture in Europe (1990-2015) and Slovenia (1986-2017) and their changes in the period under review. Both agriculture in Europe and in Slovenia contributes around 10 % to total GHG emissions. In Europe, emissions decreased by 20 % during the period considered, mainly due reduced use of nitrogen fertilizers and a reduction in livestock numbers. In Slovenia, most GHG emissions from agriculture are caused by methane (CH4) and nitrous di-oxide (N2O) in the process of fermentation in livestock farming, improper manure storage and improper soil management. CH4 emissions from agriculture account for 50 % and N2O for 71 % of total emissions in the country. Nitric oxide, ammonia, volatile organic compounds and carbon dioxide also account for an important part of agricultural emissions. In the period 1986-2017, emissions from agriculture in Slovenia decreased by 20 % due to a 50 % reduction in fuel emissions and a 25% reduction in manure storage emissions. GHG emissions from agriculture in Slovenia are in accordance with the set goal of controlling the increase in emissions by 2020 to a maximum of 5 % compared to 2005. Nevertheless, it is necessary to introduce good agricultural practices to reduce GHG emissions in order to minimize the impact of agriculture on climate change.