Abstract:[Objective] The relationship between litter decomposition characteristics and soil nutrient characteristics of Abies georgei var. smithii forest in Southeastern Tibet under different habitat conditions, i.e., in forest (IF), outside forest (OF), and beside forest (BF) was studied to provide basic data for further understanding the material circulation process of the alpine forest ecosystem.[Methods] Based on field decomposition bag method and indoor analysis, in situ decomposition experiments were conducted on A. georgei forest litters in Southeast Tibet under three different habitats.[Results] The decomposition rate showed the characteristics of IF > BF > OF, and the variation coefficient of the monthly decomposition rate represented the characteristics of IF (34.83%) < BF(57.35%) < OF (72.09%). According to the simulation results of the Olson exponential decay model, the decomposition times of litters in different habitat conditions (IF, BF, and OF) were 2.11, 2.52, and 2.34 years, respectively, and 95% of decomposition times were 8.96, 10.01, and 10.84 years, respectively. Soil nutrients in the three different habitats were significantly different in space. The soil nutrient factors in the forest habitats with significant correlation with the litter decomposition rate were soil total organic carbon (TOC) content, N content, soil microbial biomass carbon content, soil microbial biomass nitrogen content, and WC:WN value. The soil TOC content was maximum correlated with the decomposition rate of litter in the habitats outside and at forest margins, followed by WC:WN value.[Conclusion] The difference of habitat conditions had a significant impact on the decomposition rate and nutrient release rate of litters, and different soil nutrient factors played a leading role in the decomposition of litters under different habitat conditions. The litter-soil biogeochemical cycle was closely related to complex interaction and a prominent habitat effect.