It is difficult to measure the physical property of sliding surface directly, especially for flat zone (deposition zone) due to the obstacles such as road, houses, tree and so on. However the run-out distance of sliding mass is affected by the frictional coefficient of flat zone. The method to evaluate the frictional coefficient on the deposit zone by applying buckling theory including self weight of landslide mass is proposed in this research. The method is consisted from two processes. Process1 is judgment of slope failure type occurring buckling failure or Rankine’s type. Procdss2 is evaluation of on the deposition zone from solving the equilibrium of landslide mass left on the slope. [This abstract is not included in the PDF]