Abstract: Thin-wall cast-in-situ tubular pile is a new type of high quality pile,which has been applied in soft ground treatment.Load transfer mechanism of tubular pile is not expatiated completely because of the complex mechonism of soil core,which restricts the development of the theory for the bearing capacity of pile and its practiceal application.With linear elasto-plastic load transfer function,a set of analytical equations for the axial load-settlement curve of thin-wall cast-in-situ tubular pile were deduced.Correlative parameters of the pile-soil system could be got from fitting of measured P—S curve,and the distribution equations of axial force and friction along pile could be calculated.Case study was given to validate the method.