In order to improve the accuracy of stress analysis of blade wheels, one way Fluid- Structure Interaction method was introduced based on the comparisons of existing methods. Finite element analysis software ANSYS along with CFD software FLUENT were comprehensively used for the strength analysis of dual-chamber couplings. According to the simulation results from CFD, the node loads at the interface of pump wheel and the working fluid were obtained and the torque and axial force were predicated. Then the static stress of pump wheel was analyzed with ANSYS. The detail processes were described in this paper. The results show that the blades of pump wheel is loaded by alternating forces, and the maximum stress, which is 64MPa, locates at the junction area of the blades and shell. And the coupling analyzed in this study meets the strength requirement.