As a result of analyzing the impeller deformation under working condition using one-way FSI simulation, the deformation has occurred from suction to pressure side at the leading edge and from pressure to suction side at trailing edge of the impeller blade. Impeller hub expands in the radial direction and moves forward to the casing near the impeller exit. In centrifugal impellers, the pressure untwist acts in the opposite direction to the blade twist caused by centrifugal force. The largest deformation has occurred at the leading edge tip of the impeller. The maximum stress took place at the blade root.