Abstract:The global environment change would affect litter decomposition and nutrient cycling directly and indirectly in forest ecosystem. The effects of global warming, elevated CO2, increased UV-B radiation and N deposition on litter decomposition was reviewed in this paper based on literatures. In general, the litter substrate quality, biotic factors such as microbe and animal, and abiotic factors including temperature, moisture and soil condition were the main factors affecting decomposition rate. Global warming made both positive and negative effects on abiotic factors. Although global warming slightly influenced the litter chemistry, however, it indirectly changed litter production, chemistry composing and decay through alter vegetation component. A temperature variable (annual mean temperature, effective temperature sum or its logarithm) combined with a summer drought indictor explained the first-year mass loss of the Scots pine needle litter across Europe and North America with a higher R2 value than actual evapotranspiration. Global warming also enhanced soil microbe activity and thereby accelerated decomposition. Elevated CO2 would increase litter production and affect decomposition by altering litter quality (e.g. improving C∶N and Lignin∶N ratio) and biotic environment such as microbe quantity and activity. Increased UV-B radiation and N deposition also affected decomposition, but the results were uncertainty as the absent of data. In addition, global environment change would obviously affect the C cycling through changing litter decomposition. Therefore, it is necessary to enhance the further research of global environment change and response of litter decomposition and the reciprocity of various factors due to the complex relationship.