In this study, a prognostic technique of the cavitation erosion for centrifugal pumps is presented. In order to estimate the erosion state of pumps, the damage rate is calculated based on the cavitation noise measurement. The accumulated damage is predicted by using the Miner"s rule and the estimated damage coping with the particular operating conditions. The remaining useful life(RUL) of pump impellers is estimated according to the accumulated damage prediction and based on the assumption for the future operating conditions. A Monte Carlo simulation is applied to obtain the prognostic uncertainty. The comparison of the prediction and the test result demonstrates that the developed method can be applied to predict cavitation erosion state and the RUL estimate.