Hydrothermal pattern and vegetation community structure are key factors affecting the soil organic carbon (SOC) formation and accumulation in alpine peatlands. Research on the influence of vegetation and soil factors on SOC spatial differentiation pattern under the thaw slump erosion gullies drainage gradient, can help understand the alpine peatlands carbon sequestration mechanism under the climate change. In this paper, experiments were conducted in drainage alpine peatlands on Zoige Plateau. From undisturbed peatland to the edge of the erosion gully formed by thaw slump, according to the water level changes. Four drainage gradient sample plots were set up successively, namely undrained (Ⅰ), lightly drained (Ⅱ), moderately drained (Ⅲ) and heavily drained (Ⅳ), the effects of community characteristics and soil factors on the SOC content at different drainage gradients were studied. The results show that: Horizontally, the dominant species succession from Carex muliensis (I) to Blysmus sinocompressus (II, III) and Kobresia tibetica (IV), the SOC, soil water content (SWC), C/N, community biomass (TB), litter count (LC), and root/shoot (R/S) decreased, the soil bulk density (BD), pH and temperature (ST) increased. Vertically, the SOC in Sample plot I decreased, in Sample plot II, III, and IV firstly decreased and then increased. The SOC was highly significant positive correlation with TB, LC, and R/S (p < = 0.01). Path analysis indicated that the order of soil factors affecting SOC was SWC > C/N > ST > BD. Drainage affects the peatlands ecohydrological processes, disrupts the balance of material input and decomposition, changes the SOC horizontal and vertical patterns, causing alpine peatlands degradation.