All turbine rotor blades are expected to be manufactured uniformly so as to form a strict circular symmetric structure, but the mistuning of turbine impeller always exists due to some factors such as the machining tolerance and running wear. In order to reduce the sensitivity of impeller to random mistuning in design,the random mistuning sensitivities of impeller designed according to three intentional mistuning patterns were analyzed based on the CMM reducedorder model and accelerated Monte Carlo simulation. The results show that the forced response sensitivity curve of pattern Ⅰ still exhibits a peak characteristic but with a decreased amplitude. The peak response amplitude of pattern Ⅱ is no longer obvious and the amplification factor of its maximal amplitude decreases from 1.86 to 1.58 when compared with the tuned turbine. The designed pattern Ⅲ results in a dramatic decrease of response amplitude and the amplification factor is only 1.49. The response amplitude of pattern Ⅲis small for slight mistuning and thus not susceptible to mistuning.