Abstract: The denoise of vibration signal in engine rotor system is proposed,which is based on signal blind separation.Under the circumstance of lighter rub impact,the vibration signal contains instantaneous and high frequency weak information,and frequency mixing with the stochastic noise may take place.The classical filtering is ineffective in terms the denoise.Blind separation of sources based on higher order cumulants is applied to the separation between vibration signal and noise,which is important to diagnosis of rub impact fault.