Abstract: As the main greenhouse gases, CO₂, CH₄ and N₂O play important contribution to the global warming. Especially, agriculture as an important source of greenhouse gas emissions, plays an immeasurable role on the global warming. In general, the agroecosystem is atmospheric CO₂ and N₂O emission source, the dry land such as loess plateau is the sink of CH₄. CO₂ emissions mainly includ the respiration of plant and soil. CH₄ emissions includ two process of reduction and oxidation of CH₄. N₂O emissions includ nitrification and denitrification of two processes. Soil microbes, soil moisture, soil temperature, soil texture, fertilizing etc affect release and absorption of greenhouse gas from different angles. In recent years, some conservation tillage technology such as no-tillage, straw turnover and plastic mulches had been widespread applied in the agro-ecosystem in arid regions. The no-tillage can reduce emissions of CO₂ and N₂O, an increase the uptake of CH₄ in soil. Straw turnover promoted the CO₂ emissions and inhibited CH₄ absorption, while mulches promoted CH₄ absorption and inhibited CO₂ emissions. To provide more accurate theoretical basis for the global climate warming, a key research should be focused onstrengthening deeper and more comprehensive research on greenhouse gas emissions of agroecosystem in arid land in the future.