[Objective] To analyze the effects of vegetation degradation on litter decomposition in Gahai wetland in the Eastern Qinghai-Tibet Plateau, we aim to provide the basis for research on biogeochemical cycles of biogenic elements in wetland.[Methods] Using the litter bag technique, we examined the decomposition rates and their influencing factors in typical peatlands and swamp meadows in the Gahai wetland.[Results] There were significant differences in litter decompositions among different vegetation degradation stages. Vegetation degradation inhibited litter decomposition in general, but the responses varied with different wetland types. In the growing season (from May to September), the litter decomposition rates of undegraded healthy vegetation were significantly higher than that of degraded vegetation (P<0.05). The order of average decomposition rates in swamp meadows was, undegraded (0.028 9 g/d) > medium degraded (0.028 7 g/d) > slightly degraded (0.028 0 g/d). There were clear inter-annual variations of litter decompositions for each vegetation degradation stages. For all three years, in the growing season, the litter decomposition rates were faster in 2014 while relatively slower in 2015 and 2016. Temperature and precipitation conditions enhanced litter decomposition, but the effect was not significant.[Conclusion] The decomposition rates were simultaneously influenced by the quality of the litter, meteorological characteristics and soil environmental factors. In comparison, the effect of the quality of the litter was greater.