Foliar litter decomposition during the season with freeze-thaw cycles helps to replenish the store of nutrients necessary for ecosystem productivity for the subsequent growing season in alpine meadow ecosystems, and as such is an important process for the maintenance of materials cycling and nutrient balance in alpine meadows. However, little information is currently available about what effect soil fauna may have on foliar litter decomposition in cold-biome alpine meadow ecosystems,given that the severity of the environment during the season with freeze-thaw cycles might restrict soil fauna activity. To examine the possible influence of soil fauna, we conducted a field experiment in an alpine meadow in southwestern Sichuan,China,using litterbags of different mesh sizes to exclude or include soil fauna. The contribution of soil fauna to the foliar litter mass loss of two common plants,Ajania nubigena and Carex atrofusca,was examined during three distinct periods: the pre-freeze period, the freeze period, and the thaw period. Over the entirety of the season with freeze-thaw cycles, A. nubigena and C. atrofusca foliar litters lost 26.09% and 16.35% of their initial mass, respectively, in large-mesh litterbags, but lost only 14.02% and 12.31% of their initial mass, respectively, in small-mesh litterbags. However, the contribution of soil fauna to the foliar litter mass loss of two common plants, A. nubigena and C. atrofusca, were 46.39% and 25.14%, respectively, and the mass loss rates driven by soil fauna were 12.07% and 4.03%, respectively, during the season with freeze-thaw cycles. Compared with other periods,rates of foliar litter mass loss driven by soil fauna were highest in the thaw period for both A. nubigena and C. atrofusca. On the other hand, the lowest rates of mass loss driven by soil fauna occurred in the pre-freeze period for A. nubigena foliar litter but during the freeze period for C. atrofusca foliar litter. Moreover, it is notable that soil fauna negatively affected foliar litter mass loss in the pre-freeze period but positively impacted foliar litter in both the freeze and thaw periods. In addition, the rate of mass loss attributable to soil fauna was significantly (P< 0.05) correlated with temperature and initial foliar litter quality, such as initial carbon (C) and nitrogen (N) concentrations and the C/N ratio during the season with freeze-thaw cycles. Loss of foliar litter mass was also significantly (P< 0.05) influenced by the interactions between litterbag mesh size and litter decomposition period. Soil fauna also seemed to play a more active role in A. nubigena foliar litter decomposition than in C. atrofusca foliar litter decomposition. These results indicated that although soil fauna play a large role in the decomposition of foliar litter during the season with freeze-thaw cycles in alpine meadow ecosystems, this process is modulated by the dynamics of the freezethaw cycle and the initial quality of the foliar litter. A shorter period of snow cover or reduction in snow depth resulting from climate change could affect soil fauna activity and thus the rates of foliar litter decomposition in these alpine environments.