[Background] Collapsing mound, called “Benggang冶by local residents which originated from Chinese geomorphic pictograph, has been known to describe an erosion phenomenon in hilly area in subtropical and some tropical climatic zone of southeast China where the edge of gully source collapses and develops a deep-seated shape landform with deep-cut concave. Under the pressure of loose and barren surface soil with high acidity, as well as low vegetation coverage by deforestation, a collapsing hill is vulnerable to degenerate into eroded badland. [Methods] To reveal the effect of soil physical chemical property and erodibility from collapsing mound, three typical collapse mounds (No. 1, No. 2 and No. 3 representing the vegetation coverage in the range of 2%, 20% and 95%, respectively ) being selected within Huangnikeng collapse mound group of Zhuotian Town, Changting County in southwestern Fujian Province, basic soil physical property from the system of collapse mound including upper catchment, collapsing wall, colluvial deposit and channel outlet were investigated and measured, and erodibility K value were also calculated applying the model of Erosion Productivity Impact Calculator (EPIC). [Results] 1) For these three collapse mounds with different vegetation coverage, soil sand content, pH and bulk density had an increasing trend from upper catchment, collapsing wall, colluvial deposit till channel outlet, however, soil silt content, clay content and moisture content were descended. 2) Soil organic matter content of collapse mound No. 1 and No. 2 were the highest at upper catchment, and the lowest at collapsing wall; soil organic matter content of collapse mound No. 3 declined sharply at collapsing wall and increased significantly at colluvial deposit. 3) Little variation of soil particle composition, bulk density and content existed in upper catchment, collapsing wall and colluvial deposit among three collapse mounds, and all indicators of soil physical properties existed obvious difference between channel outlet and upper catchment, collapsing wall, colluvial deposit. 4 ) There were significant differences of K value among upper catchment, collapsing wall, colluvial deposit, channel outlet, and the K value of collapse mound No. 1 and collapse mound No. 2 declined in order of collapsing wall > colluvial deposit > channel outlet > upper catchment, but collapse mound No. 3 declined in order of channel outlet > colluvial deposit > collapsing wall > upper catchment. 5) The clay content, pH value, and organic matter content could be cited as the valid index to determine the intensity of soil erosion in the area of collapse mound, since they were close correlation with K value. [Conclusions] In summary, collapse mound erosion caused deterioration of soil physical properties and severe sandy associated with relative high magnitude of erodibility K value; studying the spatial differentiation on soil physical properties and erodibility in the eroded area of collapse mound erosion system presented important significance in the restoration and reconstruction in the degraded ecosystem of eroded red soil region.