Abstract: This paper studies dynamic characteristics of a power turbine rotor of a new-type turbine shaft engine when finite element method is used.The dynamic characteristics of the rotor in different conditions,such as critical speeds,vibration shapes and unbalance responses,are respectively systematically calculated and analyzed.The first five-stage critical speeds,the curves of the first five-stage dominant vibration shapes and the first two-stage unbalance responses of the rotor are obtained.Furthermore,the influences of balance collars on dynamic characteristics of the rotor are also calculated.The experimental results show that the calculation model can factually express the dynamic characteristics of the rotor.This study provides references and bases for subsequent high speed dynamic balance of the rotor.