Abstract: Considering the interaction among pile-support,piles and soil and the elastoplastic property of soil,pile-support system is researched by three-dimensional non-linear finite element method.The change of soil non-uniform settlement with increase of load,pile counterforce development and stress distributing in the pile-support and link beam are researched.The working behavior of pile-support system is defined.The secondary stress for the non-uniform settlement is further studied and the effect of the non-uniform settlement is got.It is pointed out the rational piles and the decreases of asymmetric settlement are the effective methods to reduce the secondary stress and the steel ratio of platform and avoid inconvenience of construction。