Abstract The energy-storage flywheel system has been becoming a kind of energy storage device with broad application prospect. It has the advantages of high energy storage density, high power, high efficiency, short charging time, long life, etc. In order to prevent energy storage flywheel system components deformation or failure under high speed, the static characteristic analyses on the flywheel rotor were done respectively under two types of the permanent magnet don’t act on the rotor internal wall and the permanent magnet acts on the rotor internal wall, the deformation, equivalent stress, tangential stress, radial stress of the rotor were researched. The work can provides certain reference for the structure design, optimization design of the flywheel system.