Abstract: The stability of the flexible support of boiler feed pump turbine (BFPT) is related to the safety of power generation units. First, the mechanical boundary conditions of the flexible support were performed. Then, based on the stability theory, the flexible support was modeled according to the experimental conditions. The stability experiment of a modeled structure was carried out, in which the different eccentric displacements were concerned. In addition, three-dimensional finite element software ANSYS 11.0 was adopted to investigate the nonlinear stability of the modeled structure. Finally, the numerical results were compared with the experimental results, and the load-displacement curves from numerical results are in good agreement with that from the experimental results. It is revealed that the critical load of the modeled structure decreases with the increase of displacement eccentricity. The validity of the method used to analyze the nonlinear stability of the flexible support is verified by the numerical simulation and experimental validation on a modeled structure, thus provides the basis of researching the stability of the actual flexible support structures and the stability of BFPT.