Abstract: A micro turbine jet engine,as a research object,was studied in order to conduct the design process and methods of micro turbine jet engine rotor system.Firstly,this paper introduced the engine and it's rotor system structures,generalized the design principles of rotor system,and then emphasized the design process of rotor system from bearing choices,rotor dynamic characteristics,vibration absorber techniques,rotor dynamic balance and bearing failure formats.These design experiences can be references for improving design ability of domestic micro turbine jet engine.