[Objective] The changes of soil physical and chemical properties in three levels of degraded grasslands(light degradation grasslands

middle degradation grasslands and heavy degradation grasslands) in alpine grassland in the Qilian Mountain were studied to provide references for the restoration of grasslands in analogous area. [Methods] Vegetation investigation and soil sampling were conducted and the samples were assayed. [Results] Obvious differences were observed in community composition and species diversity. The soil physical and chemical properties under different degraded grasslands were affected by degradation level. The soil bulk density in the heavy degraded grassland was significantly higher(p<0.05) than that of light degraded grassland. The content of soil total porosity of 0-10 cm layer in light degradation grassland was significantly higher than that of heavy degraded grassland. The contents of organic matter

total K

total P and available K in heavy degraded grassland were obviously lower(p<0.05) than those of lighter degraded grassland

but there were no significant differences in the content of pH value and available N. [Conclusion] Soil physical and chemical characteristics were significantly affected by vegetation degraded succession in alpine grassland.