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A fast reanalysis method for structures with nonlinear supports is developed based on Indirect Factorization Updating (IFU) in this study. The famous Newton-Ralfson’s method is employed to solve the nonlinear equation, therefore, the tangent stiffness matrix should be calculated and factorized repeatedly in the iterative process. The nonlinearity of the supports as well as structural modifications will lead to change of tangent stiffness matrix. In order to improve the efficiency of solving process, the IFU method is applied to deal with the change of tangent stiffness matrix. The numerical example shows that the proposed method is effective for structures with nonlinear supports.